Guide to the Secure Configuration of Red Hat Enterprise Linux 7

with profile WebCS changes to the pre-release Draft STIG for CentOS Linux 7 Server
This profile developed by Astronics Ballard Technology for the WebCS

This guide presents a catalog of security-relevant configuration settings for Red Hat Enterprise Linux 7 formatted in the eXtensible Configuration Checklist Description Format (XCCDF).

Providing system administrators with such guidance informs them how to securely configure systems under their control in a variety of network roles. Policy makers and baseline creators can use this catalog of settings, with its associated references to higher-level security control catalogs, in order to assist them in security baseline creation. This guide is a catalog, not a checklist, and satisfaction of every item is not likely to be possible or sensible in many operational scenarios. However, the XCCDF format enables granular selection and adjustment of settings, and their association with OVAL and OCIL content provides an automated checking capability. Transformations of this document, and its associated automated checking content, are capable of providing baselines that meet a diverse set of policy objectives. Some example XCCDF Profiles, which are selections of items that form checklists and can be used as baselines, are available with this guide. They can be processed, in an automated fashion, with tools that support the Security Content Automation Protocol (SCAP). The DISA STIG for Red Hat Enterprise Linux 7 is one example of a baseline created from this guidance.

This benchmark is a direct port of a SCAP Security Guide benchmark developed for Red Hat Enterprise Linux. It has been modified through an automated process to remove specific dependencies on Red Hat Enterprise Linux and to function with CentOS. The result is a generally useful SCAP Security Guide benchmark with the following caveats:

  • CentOS is not an exact copy of Red Hat Enterprise Linux. There may be configuration differences that produce false positives and/or false negatives. If this occurs please file a bug report.
  • CentOS has its own build system, compiler options, patchsets, and is a community supported, non-commercial operating system. CentOS does not inherit certifications or evaluations from Red Hat Enterprise Linux. As such, some configuration rules (such as those requiring FIPS 140-2 encryption) will continue to fail on CentOS.

Members of the CentOS community are invited to participate in OpenSCAP and SCAP Security Guide development. Bug reports and patches can be sent to GitHub: https://github.com/OpenSCAP/scap-security-guide. The mailing list is at https://fedorahosted.org/mailman/listinfo/scap-security-guide.

Do not attempt to implement any of the settings in this guide without first testing them in a non-operational environment. The creators of this guidance assume no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic.

Evaluation Characteristics

Target machinedevgobah
Benchmark URL/usr/share/xml/scap/ssg/content/ssg-webcs-ds.xml
Benchmark IDxccdf_org.ssgproject.content_benchmark_RHEL-7
Profile IDxccdf_org.ssgproject.content_profile_stig-webcs
Started at2016-07-11T14:18:32
Finished at2016-07-11T14:24:58
Performed byadmin

CPE Platforms

  • cpe:/o:centos:centos:7
  • cpe:/o:redhat:enterprise_linux:7
  • cpe:/o:redhat:enterprise_linux:7::client
  • cpe:/o:redhat:enterprise_linux:7::computenode

Addresses

  • IPv4  127.0.0.1
  • IPv4  172.30.25.53
  • IPv4  10.0.0.1
  • IPv6  0:0:0:0:0:0:0:1
  • IPv6  fe80:0:0:0:213:95ff:fe1e:ba56
  • IPv6  fe80:0:0:0:8625:3fff:fe19:b72f
  • MAC  00:00:00:00:00:00
  • MAC  00:13:95:1E:BA:56
  • MAC  84:25:3F:19:B7:2F

Compliance and Scoring

The target system did not satisfy the conditions of 24 rules! Furthermore, the results of 10 rules were inconclusive. Please review rule results and consider applying remediation.

Rule results

260 passed
24 failed
47 other

Severity of failed rules

0 other
12 low
12 medium
0 high

Score

Scoring systemScoreMaximumPercent
urn:xccdf:scoring:default86.217949100.000000
86.22%

Rule Overview

Group rules by:
TitleSeverityResult
Guide to the Secure Configuration of Red Hat Enterprise Linux 7 24x fail 10x error 37x notchecked
Remediation functions used by the SCAP Security Guide Project
Introduction
General Principles
Encrypt Transmitted Data Whenever Possible
Minimize Software to Minimize Vulnerability
Run Different Network Services on Separate Systems
Configure Security Tools to Improve System Robustness
Least Privilege
How to Use This Guide
Read Sections Completely and in Order
Test in Non-Production Environment
Root Shell Environment Assumed
Formatting Conventions
Reboot Required
System Settings 11x fail 6x error 10x notchecked
Installing and Maintaining Software 1x fail 3x error 2x notchecked
Disk Partitioning 1x notchecked
Ensure /tmp Located On Separate Partitionlow
pass
Ensure /var Located On Separate Partitionlow
pass
Ensure /var/log Located On Separate Partitionlow
pass
Ensure /var/log/audit Located On Separate Partitionlow
pass
Ensure /home Located On Separate Partitionlow
pass
Encrypt Partitionsmedium
notchecked
Updating Software 1x notchecked
Ensure Red Hat GPG Key Installedhigh
pass
Ensure gpgcheck Enabled In Main Yum Configurationhigh
pass
Ensure gpgcheck Enabled For All Yum Package Repositorieshigh
pass
Ensure Software Patches Installedhigh
notchecked
Ensure YUM Removes Previous Package Versionslow
pass
Ensure gpgcheck Enabled for Local Packageshigh
pass
Software Integrity Checking 1x fail 3x error
Verify Integrity with AIDE
Install AIDEmedium
pass
Build and Test AIDE Databasemedium
pass
Configure Periodic Execution of AIDEmedium
pass
Verify Integrity with RPM 1x error
Verify and Correct File Permissions with RPMhigh
error
Verify File Hashes with RPMhigh
pass
Additional Security Software
Install Intrusion Detection Softwarehigh
notselected
Install Virus Scanning Softwarelow
notselected
McAfee Security Software
Install McAfee Host-Based Intrusion Detection Software (HBSS)medium
notselected
Install McAfee Virus Scanning Softwarehigh
notselected
Enable nails Servicemedium
notselected
Virus Scanning Software Definitions Are Updatedmedium
notselected
Federal Information Processing Standard (FIPS) 1x fail 1x error
Install the dracut-fips Packagemedium
fail
Enable FIPS Mode in GRUB2medium
error
ID: xccdf_org.ssgproject.content_group_certified-vendor
The Installed Operating System Is Vendor Supported and Certifiedhigh
notselected
Disable Prelinkinglow
error
GNOME Desktop Environment
Disable the GNOME3 Login User Listmedium
notselected
Disable the GNOME3 Login Restart and Shutdown Buttonshigh
notselected
Enable the GNOME3 Login Smartcard Authenticationmedium
notselected
Configure GNOME Screen Locking
Set GNOME3 Screensaver Inactivity Timeoutmedium
notselected
Enable GNOME3 Screensaver Idle Activationmedium
notselected
Enable GNOME3 Screensaver Lock After Idle Periodmedium
notselected
Implement Blank Screensaverlow
notselected
GNOME System Settings
Disable Ctrl-Alt-Del Reboot Key Sequence in GNOME3high
notselected
Disable User Administration in GNOME3high
notselected
Disable Power Settings in GNOME3medium
notselected
Disable Geolocation in GNOME3medium
notselected
GNOME Network Settings
Disable WIFI Network Connection Creation in GNOME3medium
notselected
Disable WIFI Network Notification in GNOME3medium
notselected
GNOME Remote Access Settings
Require Credential Prompting for Remote Access in GNOME3medium
notselected
Require Encryption for Remote Access in GNOME3medium
notselected
GNOME Media Settings
Disable GNOME3 Automountinglow
notselected
Disable All GNOME3 Thumbnailerslow
notselected
Sudo
Ensure NOPASSWD Is Not Used in Sudomedium
pass
Ensure !authenticate Is Not Used in Sudomedium
pass
File Permissions and Masks 2x fail 2x error 1x notchecked
Restrict Partition Mount Options 1x fail 1x error
Add nodev Option to Non-Root Local Partitionslow
fail
Add nodev Option to Removable Media Partitionslow
pass
Add noexec Option to Removable Media Partitionslow
pass
Add nosuid Option to Removable Media Partitionslow
pass
Add nodev Option to /tmplow
pass
Add noexec Option to /tmplow
pass
Add nosuid Option to /tmplow
pass
Add nodev Option to /dev/shmlow
notselected
Add noexec Option to /dev/shmlow
notselected
Add nosuid Option to /dev/shmlow
notselected
Bind Mount /var/tmp To /tmplow
error
Restrict Dynamic Mounting and Unmounting of Filesystems
Disable Modprobe Loading of USB Storage Drivermedium
notselected
Disable Kernel Support for USB via Bootloader Configurationlow
notselected
Disable Booting from USB Devices in Boot Firmwarelow
notselected
Assign Password to Prevent Changes to Boot Firmware Configurationlow
notselected
Disable the Automountermedium
notselected
Disable Mounting of cramfslow
pass
Disable Mounting of freevxfslow
pass
Disable Mounting of jffs2low
pass
Disable Mounting of hfslow
pass
Disable Mounting of hfspluslow
pass
Disable Mounting of squashfslow
pass
Disable Mounting of udflow
pass
Verify Permissions on Important Files and Directories 1x fail
Verify User Who Owns shadow Filemedium
pass
Verify Group Who Owns shadow Filemedium
pass
Verify Permissions on shadow Filemedium
pass
Verify User Who Owns group Filemedium
pass
Verify Group Who Owns group Filemedium
pass
Verify Permissions on group Filemedium
pass
Verify User Who Owns gshadow Filemedium
pass
Verify Group Who Owns gshadow Filemedium
pass
Verify Permissions on gshadow Filemedium
pass
Verify User Who Owns passwd Filemedium
pass
Verify Group Who Owns passwd Filemedium
pass
Verify Permissions on passwd Filemedium
pass
Verify File Permissions Within Some Important Directories
Verify that Shared Library Files Have Restrictive Permissionsmedium
pass
Verify that Shared Library Files Have Root Ownershipmedium
pass
Verify that System Executables Have Restrictive Permissionsmedium
pass
Verify that System Executables Have Root Ownershipmedium
pass
Verify that All World-Writable Directories Have Sticky Bits Setlow
pass
Ensure No World-Writable Files Existmedium
pass
Ensure All SGID Executables Are Authorizedlow
pass
Ensure All SUID Executables Are Authorizedlow
fail
Ensure All Files Are Owned by a Usermedium
pass
Ensure All Files Are Owned by a Groupmedium
pass
Ensure All World-Writable Directories Are Owned by a System Accountlow
pass
Restrict Programs from Dangerous Execution Patterns 1x error 1x notchecked
Daemon Umask
Set Daemon Umasklow
pass
Disable Core Dumps
Disable Core Dumps for All Userslow
pass
Disable Core Dumps for SUID programslow
pass
Enable ExecShield 1x error
Enable ExecShieldmedium
pass
Enable Randomized Layout of Virtual Address Spacemedium
error
Enable Execute Disable (XD) or No Execute (NX) Support on x86 Systems 1x notchecked
Install PAE Kernel on Supported 32-bit x86 Systemslow
pass
Enable NX or XD Support in the BIOSlow
notchecked
Restrict Access to Kernel Message Bufferlow
pass
SELinux 1x fail
Ensure SELinux Not Disabled in /etc/default/grubmedium
pass
Ensure SELinux State is Enforcingmedium
pass
Configure SELinux Policylow
pass
Uninstall setroubleshoot Packagelow
pass
Uninstall mcstrans Packagelow
pass
Ensure No Daemons are Unconfined by SELinuxmedium
notselected
Ensure No Device Files are Unlabeled by SELinuxlow
fail
Account and Access Control 2x fail 1x error 3x notchecked
Protect Accounts by Restricting Password-Based Login 3x notchecked
Restrict Root Logins 2x notchecked
Direct root Logins Not Allowedmedium
pass
Restrict Serial Port Root Loginslow
pass
Restrict Web Browser Use for Administrative Accountslow
notchecked
Ensure that System Accounts Do Not Run a Shell Upon Loginmedium
pass
Verify Only Root Has UID 0high
pass
Root Path Must Be Vendor Defaultlow
notchecked
Verify Proper Storage and Existence of Password Hashes
Prevent Log In to Accounts With Empty Passwordhigh
pass
Verify All Account Password Hashes are Shadowedmedium
pass
All GIDs referenced in /etc/passwd must be defined in /etc/grouplow
pass
Verify No netrc Files Existmedium
pass
Set Password Expiration Parameters
Protect Accounts by Configuring PAM 1x error
Set Password Quality Requirements 1x error
Set Password Quality Requirements with pam_pwquality 1x error
Set Password Retry Prompts Permitted Per-Sessionlow
notselected
Set Password to Maximum of Three Consecutive Repeating Charactersmedium
pass
Set Password to Maximum of Consecutive Repeating Characters from Same Character Classlow
error
Set Password Strength Minimum Digit Charactersmedium
pass
Set Password Minimum Lengthmedium
pass
Set Password Strength Minimum Uppercase Characterslow
pass
Set Password Strength Minimum Special Charactersmedium
pass
Set Password Strength Minimum Lowercase Charactersmedium
pass
Set Password Strength Minimum Different Charactersmedium
pass
Set Password Strength Minimum Different Categoriesmedium
pass
Set Lockouts for Failed Password Attempts
Set Deny For Failed Password Attemptsmedium
pass
Set Lockout Time For Failed Password Attemptsmedium
pass
Configure the root Account for Failed Password Attemptsmedium
notselected
Set Interval For Counting Failed Password Attemptsmedium
pass
Limit Password Reusemedium
pass
Set Password Hashing Algorithm
Set PAM's Password Hashing Algorithmmedium
pass
Set Password Hashing Algorithm in /etc/login.defsmedium
pass
Set Password Hashing Algorithm in /etc/libuser.confmedium
pass
Secure Session Configuration Files for Login Accounts 2x fail
Ensure that No Dangerous Directories Exist in Root's Path
Ensure that Root's Path Does Not Include Relative Paths or Null Directorieslow
pass
Ensure that Root's Path Does Not Include World or Group-Writable Directorieslow
pass
Ensure that Users Have Sensible Umask Values
Ensure the Default Bash Umask is Set Correctlylow
pass
Ensure the Default C Shell Umask is Set Correctlylow
pass
Ensure the Default Umask is Set Correctly in /etc/profilelow
pass
Set Interactive Session Timeoutmedium
notselected
Ensure the Logon Failure Delay is Set Correctly in login.defslow
fail
Ensure that User Home Directories are not Group-Writable or World-Readablelow
fail
Protect Physical Console Access
Set Boot Loader Password
Verify /boot/grub2/grub.cfg User Ownershipmedium
pass
Verify /boot/grub2/grub.cfg Group Ownershipmedium
pass
Verify /boot/grub2/grub.cfg Permissionsmedium
pass
Set Boot Loader Passwordmedium
notselected
Set the UEFI Boot Loader Passwordmedium
notselected
Configure Screen Locking
Configure Console Screen Locking
Install the screen Packagemedium
pass
Enable Smart Card Loginmedium
notselected
Require Authentication for Single User Modemedium
pass
Disable debug-shell SystemD Servicemedium
pass
Disable Ctrl-Alt-Del Reboot Activationhigh
pass
Verify that Interactive Boot is Disabledmedium
pass
Warning Banners for System Accesses
Enable GNOME3 Login Warning Bannermedium
notselected
Modify the System Login Bannermedium
pass
Network Configuration and Firewalls 5x fail 1x notchecked
Disable Unused Interfaces
Kernel Parameters Which Affect Networking
Network Parameters for Hosts Only
Disable Kernel Parameter for Sending ICMP Redirects by Defaultmedium
pass
Disable Kernel Parameter for Sending ICMP Redirects for All Interfacesmedium
pass
Disable Kernel Parameter for IP Forwardingmedium
pass
Network Related Kernel Runtime Parameters for Hosts and Routers
Configure Kernel Parameter for Accepting Source-Routed Packets for All Interfacesmedium
pass
Configure Kernel Parameter for Accepting ICMP Redirects for All Interfacesmedium
pass
Configure Kernel Parameter for Accepting Secure Redirects for All Interfacesmedium
pass
Configure Kernel Parameter to Log Martian Packetslow
pass
Configure Kernel Parameter to Log Martian Packets By Defaultlow
pass
Configure Kernel Parameter for Accepting Source-Routed Packets By Defaultmedium
pass
Configure Kernel Parameter for Accepting ICMP Redirects By Defaultmedium
pass
Configure Kernel Parameter for Accepting Secure Redirects By Defaultmedium
pass
Configure Kernel Parameter to Ignore ICMP Broadcast Echo Requestsmedium
pass
Configure Kernel Parameter to Ignore Bogus ICMP Error Responseslow
pass
Configure Kernel Parameter to Use TCP Syncookiesmedium
pass
Configure Kernel Parameter to Use Reverse Path Filtering for All Interfacesmedium
pass
Configure Kernel Parameter to Use Reverse Path Filtering by Defaultmedium
pass
Wireless Networking
Disable Wireless Through Software Configuration
Disable WiFi or Bluetooth in BIOSlow
notselected
Deactivate Wireless Network Interfaceslow
notselected
Disable Bluetooth Servicemedium
pass
Disable Bluetooth Kernel Modulesmedium
pass
IPv6 5x fail
Disable Support for IPv6 Unless Needed
Disable IPv6 Networking Support Automatic Loadingmedium
notselected
Disable Interface Usage of IPv6low
notselected
Disable Support for RPC IPv6low
notselected
Configure IPv6 Settings if Necessary 5x fail
Disable Automatic Configuration 2x fail
Configure Kernel Parameter for Accepting Source-Routed Packets for All Interfacesmedium
pass
Configure Accepting IPv6 Router Advertisementslow
pass
Configure Accepting IPv6 Router Advertisementslow
pass
Configure Accepting IPv6 Redirects By Defaultmedium
pass
Configure Accepting IPv6 Redirects By Defaultmedium
pass
Configure Kernel Parameter for Accepting Source-Routed Packets for Interfaces By Defaultmedium
fail
Disable Kernel Parameter for IPv6 Forwardingmedium
fail
Limit Network-Transmitted Configuration if Using Static IPv6 Addresses
Manually Assign Global IPv6 Addresslow
fail
Use Privacy Extensions for Addresslow
fail
Manually Assign IPv6 Router Addresslow
fail
firewalld
Inspect and Activate Default firewalld Rules
Verify firewalld Enabledmedium
pass
Strengthen the Default Ruleset
Set Default firewalld Zone for Incoming Packetsmedium
notselected
Transport Layer Security Support
Uncommon Network Protocols
Disable DCCP Supportmedium
pass
Disable SCTP Supportmedium
pass
IPSec Support 1x notchecked
Install libreswan Packagemedium
pass
Verify Any Configured IPSec Tunnel Connectionsmedium
notchecked
Disable Client Dynamic DNS Updatesmedium
notselected
Disable Zeroconf Networkinglow
pass
Ensure System is Not Acting as a Network Snifferlow
pass
Configure Syslog 3x notchecked
Ensure Proper Configuration of Log Files
Ensure Log Files Are Owned By Appropriate Usermedium
pass
Ensure Log Files Are Owned By Appropriate Groupmedium
pass
Ensure System Log Files Have Correct Permissionsmedium
fixed
Rsyslog Logs Sent To Remote Host
Ensure Logs Sent To Remote Hostlow
notselected
Configure rsyslogd to Accept Remote Messages If Acting as a Log Server 2x notchecked
Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Serverlow
pass
Enable rsyslog to Accept Messages via TCP, if Acting As Log Serverlow
notchecked
Enable rsyslog to Accept Messages via UDP, if Acting As Log Serverlow
notchecked
Ensure All Logs are Rotated by logrotate
Ensure Logrotate Runs Periodicallylow
pass
Configure Logwatch on the Central Log Server
Configure Logwatch HostLimit Linelow
notselected
Configure Logwatch SplitHosts Linelow
notselected
Ensure rsyslog is Installedmedium
pass
Enable rsyslog Servicemedium
pass
Disable Logwatch on Clients if a Logserver Existslow
notchecked
System Accounting with auditd
Configure auditd Data Retention
Configure auditd Number of Logs Retainedmedium
pass
Configure auditd Max Log File Sizemedium
pass
Configure auditd max_log_file_action Upon Reaching Maximum Log Sizemedium
pass
Configure auditd space_left Action on Low Disk Spacemedium
pass
Configure auditd admin_space_left Action on Low Disk Spacemedium
pass
Configure auditd mail_acct Action on Low Disk Spacemedium
pass
Configure auditd flush prioritylow
pass
Configure auditd to use audispd's syslog pluginmedium
pass
Configure auditd Rules for Comprehensive Auditing
Records Events that Modify Date and Time Information
Record attempts to alter time through adjtimexlow
pass
Record attempts to alter time through settimeofdaylow
pass
Record Attempts to Alter Time Through stimelow
pass
Record Attempts to Alter Time Through clock_settimelow
pass
Record Attempts to Alter the localtime Filelow
pass
Record Events that Modify the System's Discretionary Access Controls
Record Events that Modify the System's Discretionary Access Controls - chmodlow
pass
Record Events that Modify the System's Discretionary Access Controls - chownlow
pass
Record Events that Modify the System's Discretionary Access Controls - fchmodlow
pass
Record Events that Modify the System's Discretionary Access Controls - fchmodatlow
pass
Record Events that Modify the System's Discretionary Access Controls - fchownlow
pass
Record Events that Modify the System's Discretionary Access Controls - fchownatlow
pass
Record Events that Modify the System's Discretionary Access Controls - fremovexattrlow
pass
Record Events that Modify the System's Discretionary Access Controls - fsetxattrlow
pass
Record Events that Modify the System's Discretionary Access Controls - lchownlow
pass
Record Events that Modify the System's Discretionary Access Controls - lremovexattrlow
pass
Record Events that Modify the System's Discretionary Access Controls - lsetxattrlow
pass
Record Events that Modify the System's Discretionary Access Controls - removexattrlow
pass
Record Events that Modify the System's Discretionary Access Controls - setxattrlow
pass
Record Events that Modify User/Group Informationlow
pass
Record Events that Modify the System's Network Environmentlow
pass
System Audit Logs Must Have Mode 0640 or Less Permissivemedium
pass
System Audit Logs Must Be Owned By Rootmedium
pass
Record Events that Modify the System's Mandatory Access Controlslow
pass
Record Attempts to Alter Process and Session Initiation Informationlow
pass
Ensure auditd Collects Unauthorized Access Attempts to Files (unsuccessful)medium
pass
Ensure auditd Collects Information on the Use of Privileged Commandsmedium
pass
Ensure auditd Collects Information on Exporting to Media (successful)medium
pass
Ensure auditd Collects File Deletion Events by Usermedium
pass
Ensure auditd Collects System Administrator Actionslow
pass
Ensure auditd Collects Information on Kernel Module Loading and Unloadingmedium
pass
Make the auditd Configuration Immutablelow
pass
Enable auditd Servicemedium
pass
Enable Auditing for Processes Which Start Prior to the Audit Daemonmedium
pass
Services 13x fail 4x error 27x notchecked
Obsolete Services
Xinetd
Disable xinetd Servicemedium
pass
Uninstall xinetd Packagelow
pass
Install tcp_wrappers Packagemedium
notselected
Telnet
Disable telnet Servicehigh
pass
Uninstall telnet-server Packagehigh
pass
Remove telnet Clientslow
pass
Rlogin, Rsh, and Rexec
Uninstall rsh-server Packagehigh
pass
Disable rexec Servicehigh
pass
Disable rsh Servicehigh
pass
Uninstall rsh Packagelow
pass
Disable rlogin Servicehigh
pass
Remove Rsh Trust Fileshigh
pass
NIS
Uninstall ypserv Packagehigh
pass
Disable ypbind Servicemedium
pass
Remove NIS Clientlow
pass
TFTP Server
Disable tftp Servicemedium
pass
Uninstall tftp-server Packagehigh
pass
Remove tftp Daemonhigh
pass
Ensure tftp Daemon Uses Secure Modehigh
notselected
Chat/Messaging Services
Uninstall talk-server Packagemedium
pass
Uninstall talk Packagelow
pass
Base Services 1x error
Disable Automatic Bug Reporting Tool (abrtd)low
pass
Disable Advanced Configuration and Power Interface (acpid)low
pass
Disable Certmonger Service (certmonger)low
pass
Disable Control Group Config (cgconfig)low
pass
Disable Control Group Rules Engine (cgred)low
pass
Disable CPU Speed (cpupower)low
notselected
Enable IRQ Balance (irqbalance)low
pass
Disable KDump Kernel Crash Analyzer (kdump)medium
pass
Disable Software RAID Monitor (mdmonitor)low
pass
Disable D-Bus IPC Service (messagebus)low
pass
Disable Network Console (netconsole)low
pass
Disable ntpdate Service (ntpdate)low
pass
Disable Odd Job Daemon (oddjobd)low
pass
Disable Portreserve (portreserve)low
pass
Enable Process Accounting (psacct)low
error
Disable Apache Qpid (qpidd)low
pass
Disable Quota Netlink (quota_nld)low
pass
Disable Network Router Discovery Daemon (rdisc)low
pass
Disable Red Hat Network Service (rhnsd)low
pass
Disable Red Hat Subscription Manager Daemon (rhsmcertd)low
pass
Disable Cyrus SASL Authentication Daemon (saslauthd)low
pass
Disable SMART Disk Monitoring Service (smartd)low
pass
Disable System Statistics Reset Service (sysstat)low
pass
Cron and At Daemons 1x notchecked
Restrict at and cron to Authorized Users if Necessary
Enable cron Servicemedium
pass
Disable anacron Servicelow
notchecked
Disable At Service (atd)low
pass
SSH Server 8x fail 2x error 1x notchecked
Configure OpenSSH Server if Necessary 6x fail 2x error 1x notchecked
Strengthen Firewall Configuration if Possible
Allow Only SSH Protocol 2high
pass
Limit Users' SSH Accesslow
notchecked
Disable GSSAPI Authenticationmedium
fail
Disable Kerberos Authenticationmedium
fail
Enable Use of StictModesmedium
fail
Enable Use of Privilege Separationmedium
fail
Disable Compression Or Set Compression to delayedmedium
fail
Print Last Loglow
fail
Set SSH Idle Timeout Intervallow
pass
Set SSH Client Alive Countlow
pass
Disable SSH Support for .rhosts Filesmedium
pass
Disable Host-Based Authenticationmedium
pass
Enable Encrypted X11 Fordwardinghigh
pass
Disable SSH Access via Empty Passwordshigh
pass
Enable SSH Warning Bannermedium
pass
Do Not Allow SSH Environment Optionsmedium
pass
Use Only Approved Ciphersmedium
error
Use Only FIPS Approved MACsmedium
error
Install the OpenSSH Server Packagemedium
pass
Enable the OpenSSH Servicemedium
pass
Disable SSH Server If Possible (Unusual)low
notselected
Verify Permissions on SSH Server Public *.pub Key Filesmedium
pass
Verify Permissions on SSH Server Private *_key Key Filesmedium
fail
Remove SSH Server firewalld Firewall exception (Unusual)low
fail
System Security Services Daemon 3x fail 1x error
Install the SSSD Packagemedium
notselected
Enable the SSSD Servicemedium
error
Configure SSSD's Memory Cache to Expiremedium
fail
Configure SSSD to Expire Offline Credentialsmedium
fail
Configure SSSD to Expire SSH Known Hostsmedium
fail
X Window System
Disable X Windows
Disable X Windows Startup By Setting Default Targetmedium
notselected
Remove the X Windows Package Groupmedium
pass
Avahi Server
Disable Avahi Server if Possible
Disable Avahi Server Softwarelow
notselected
Configure Avahi if Necessary
Serve Avahi Only via Required Protocollow
notselected
Check Avahi Responses' TTL Fieldlow
notselected
Prevent Other Programs from Using Avahi's Portlow
notselected
Disable Avahi Publishinglow
notselected
Restrict Information Published by Avahilow
notselected
Print Support
Configure the CUPS Service if Necessary
Disable Printer Browsing Entirely if Possiblelow
notselected
Disable Print Server Capabilitieslow
notselected
Disable the CUPS Servicelow
notselected
DHCP 4x notchecked
Disable DHCP Server
Disable DHCP Servicemedium
notselected
Uninstall DHCP Server Packagemedium
notselected
Disable DHCP Server 4x notchecked
Minimize Served Information
Do Not Use Dynamic DNSlow
notchecked
Deny Decline Messageslow
notchecked
Deny BOOTP Querieslow
notchecked
Configure Logginglow
notchecked
Disable DHCP Client
Disable DHCP Clientlow
notselected
Configure DHCP Client if Necessary
Minimize the DHCP-Configured Options
Network Time Protocol
Enable the NTP Daemonmedium
pass
Specify a Remote NTP Servermedium
pass
Specify Additional Remote NTP Serverslow
pass
Mail Server Software
Configure SMTP For Mail Clients
Disable Postfix Network Listeningmedium
notselected
Configure Operating System to Protect Mail Server
Configure SSL Certificates for Use with SMTP AUTH
Ensure Security of Postfix SSL Certificate
Configure Postfix if Necessary
Configure Postfix Resource Usage to Limit Denial of Service Attacks
Control Mail Relaying
Configure Trusted Networks and Hosts
Enact SMTP Relay Restrictions
Enact SMTP Recipient Restrictions
Require SMTP AUTH Before Relaying from Untrusted Clients
Use TLS for SMTP AUTH
Configure SMTP Greeting Bannermedium
notselected
Enable Postfix Servicelow
notselected
Uninstall Sendmail Packagemedium
notselected
LDAP
Configure OpenLDAP Clients
Configure LDAP Client to Use TLS For All Transactionsmedium
notselected
Configure Certificate Directives for LDAP Use of TLSmedium
notselected
Configure OpenLDAP Server
Install and Protect LDAP Certificate Files
Uninstall openldap-servers Packagelow
notselected
NFS and RPC 1x notchecked
Disable All NFS Services if Possible
Disable Services Used Only by NFS
Disable Network File System Lock Service (nfslock)low
notselected
Disable Secure RPC Client Service (rpcgssd)low
notselected
Disable rpcbind Servicelow
notselected
Disable RPC ID Mapping Service (rpcidmapd)low
notselected
Configure All Machines which Use NFS
Make Each Machine a Client or a Server, not Both
Configure NFS Services to Use Fixed Ports (NFSv3 and NFSv2)
Configure lockd to use static TCP portlow
notselected
Configure lockd to use static UDP portlow
notselected
Configure statd to use static portlow
notselected
Configure mountd to use static portlow
notselected
Configure NFS Clients
Disable NFS Server Daemons
Specify UID and GID for Anonymous NFS Connectionslow
notselected
Disable Network File System (nfs)low
pass
Disable Secure RPC Server Service (rpcsvcgssd)low
pass
Mount Remote Filesystems with Restrictive Options
Mount Remote Filesystems with nodevmedium
pass
Mount Remote Filesystems with nosuidmedium
pass
Mount Remote Filesystems with Kerberos Securitymedium
pass
Configure NFS Servers 1x notchecked
Configure the Exports File Restrictively
Use Access Lists to Enforce Authorization Restrictions
Export Filesystems Read-Only if Possible
Use Root-Squashing on All Exportslow
notchecked
Restrict NFS Clients to Privileged Portslow
notselected
Ensure Insecure File Locking is Not Allowedmedium
pass
Use Kerberos Security on All Exportsmedium
pass
DNS Server 3x notchecked
Disable DNS Server
Disable DNS Serverlow
notselected
Uninstall bind Packagelow
notselected
Isolate DNS from Other Services
Run DNS Software on Dedicated Servers
Run DNS Software in a chroot Jail
Protect DNS Data from Tampering or Attack 3x notchecked
Run Separate DNS Servers for External and Internal Queries
Use Views to Partition External and Internal Information
Disable Zone Transfers from the Nameserverlow
notchecked
Authenticate Zone Transferslow
notchecked
Disable Dynamic Updateslow
notchecked
FTP Server
Disable vsftpd if Possible
Disable vsftpd Servicelow
pass
Uninstall vsftpd Packagehigh
pass
Use vsftpd to Provide FTP Service if Necessary
Install vsftpd Packagelow
notselected
Use vsftpd to Provide FTP Service if Necessary
Restrict the Set of Users Allowed to Access FTP
Limit Users Allowed FTP Access if Necessary
Restrict Access to Anonymous Users if Possiblelow
notselected
Configure Firewalls to Protect the FTP Server
Enable Logging of All FTP Transactionslow
notselected
Create Warning Banners for All FTP Usersmedium
notselected
Disable FTP Uploads if Possiblelow
notselected
Place the FTP Home Directory on its Own Partitionlow
notselected
Web Server 2x fail 17x notchecked
Disable Apache if Possible
Disable httpd Servicelow
notselected
Uninstall httpd Packagelow
notselected
Install Apache if Necessary
Confirm Minimal Built-in Modules Installed
Secure Apache Configuration 2x fail 17x notchecked
Restrict Web Server Information Leakage 2x notchecked
Set httpd ServerTokens Directive to Prodlow
notchecked
Set httpd ServerSignature Directive to Offlow
notchecked
Minimize Web Server Loadable Modules 9x notchecked
httpd Core Modules 9x notchecked
Minimize Modules for HTTP Basic Authentication
Minimize Various Optional Components
Minimize Configuration Files Included
Disable HTTP Digest Authenticationlow
notchecked
Disable HTTP mod_rewritelow
notchecked
Disable LDAP Supportlow
notselected
Disable Server Side Includeslow
notchecked
Disable MIME Magiclow
notchecked
Disable WebDAV (Distributed Authoring and Versioning)low
notselected
Disable Server Activity Statuslow
notchecked
Disable Web Server Configuration Displaylow
notchecked
Disable URL Correction on Misspelled Entrieslow
notchecked
Disable Proxy Supportlow
notselected
Disable Cache Supportlow
notchecked
Disable CGI Supportlow
notchecked
Directory Restrictions 4x notchecked
Restrict Root Directorylow
notchecked
Restrict Web Directorylow
notchecked
Restrict Other Critical Directorieslow
notchecked
Limit Available Methodslow
notchecked
Use Appropriate Modules to Improve httpd's Security 2x notchecked
Deploy mod_ssl 1x notchecked
Install mod_ssllow
notchecked
Deploy mod_security 1x notchecked
Install mod_securitylow
notchecked
Use Denial-of-Service Protection Modules
Configure PHP Securely
Configure Operating System to Protect Web Server 2x fail
Restrict File and Directory Access 2x fail
Set Permissions on the /var/log/httpd/ Directorylow
pass
Set Permissions on the /etc/httpd/conf/ Directorylow
fail
Set Permissions on All Configuration Files Inside /etc/httpd/conf/low
fail
Configure firewalld to Allow Access to the Web Server
Run httpd in a chroot Jail if Practical
IMAP and POP3 Server
Disable Dovecot
Disable Dovecot Servicelow
notselected
Uninstall dovecot Packagelow
notselected
Configure Dovecot if Necessary
Support Only the Necessary Protocols
Enable SSL Support
Enable the SSL flag in /etc/dovecot.conflow
notselected
Configure Dovecot to Use the SSL Certificate filelow
notselected
Configure Dovecot to Use the SSL Key filelow
notselected
Disable Plaintext Authenticationlow
notselected
Allow IMAP Clients to Access the Server
Network Routing
Disable Quagga if Possible
Disable Quagga Servicemedium
pass
Uninstall quagga Packagemedium
pass
Samba(SMB) Microsoft Windows File Sharing Server
Disable Samba if Possible
Disable Sambalow
notselected
Uninstall Samba Packagelow
notselected
Configure Samba if Necessary
Restrict SMB File Sharing to Configured Networks
Restrict Printer Sharing
Disable Root Access to SMB Shareslow
notselected
Require Client SMB Packet Signing, if using smbclientlow
notselected
Require Client SMB Packet Signing, if using mount.cifslow
notselected
Proxy Server
Disable Squid if Possible
Disable Squidlow
notselected
Uninstall squid Packagelow
notselected
SNMP Server
Disable SNMP Server if Possible
Disable snmpd Servicelow
notselected
Uninstall net-snmp Packagelow
notselected
Configure SNMP Server if Necessary
Configure SNMP Service to Use Only SNMPv3 or Newer medium
pass
Ensure Default SNMP Password Is Not Usedhigh
pass
Documentation to Support DISA OS SRG Mapping
Product Meets this Requirementlow
notselected
Product Meets this Requirementlow
notselected
Product Meets this Requirementlow
notselected
Guidance Does Not Meet this Requirement Due to Impracticality or Scopelow
notselected
Implementation of the Requirement is Not Supportedlow
notselected
Guidance Does Not Meet this Requirement Due to Impracticality or Scopelow
notselected
A process for prompt installation of OS updates must exist.low
notselected
Documentation to Support C2S/CIS Mapping
Procedural Requirementlow
notselected
Not Applicable to Operating Systemlow
notselected
Product Meets this Requirementlow
notselected
Requirement Applies to All Ruleslow
notselected
Rule Compliance through Removal of xinetdlow
notselected

Result Details

Ensure /tmp Located On Separate Partitionxccdf_org.ssgproject.content_rule_partition_for_tmp low

Ensure /tmp Located On Separate Partition

Rule IDxccdf_org.ssgproject.content_rule_partition_for_tmp
Result
pass
Time2016-07-11T14:18:34
Severitylow
Identifiers and References

identifiers: 

references:  SC-32(1), 366, SRG-OS-000480-GPOS-00227, 1.1.1, RHEL-07-021270, Test attestation on 20120928 by MM

Description

The /tmp directory is a world-writable directory used for temporary file storage. Ensure it has its own partition or logical volume at installation time, or migrate it using LVM.

Rationale

The /tmp partition is used as temporary storage by many programs. Placing /tmp in its own partition enables the setting of more restrictive mount options, which can help protect programs which use it.

Ensure /var Located On Separate Partitionxccdf_org.ssgproject.content_rule_partition_for_var low

Ensure /var Located On Separate Partition

Rule IDxccdf_org.ssgproject.content_rule_partition_for_var
Result
pass
Time2016-07-11T14:18:34
Severitylow
Identifiers and References

identifiers: 

references:  SC-32(1), 1.1.5, 366, SRG-OS-000480-GPOS-00227, RHEL-07-021250, Test attestation on 20120928 by MM

Description

The /var directory is used by daemons and other system services to store frequently-changing data. Ensure that /var has its own partition or logical volume at installation time, or migrate it using LVM.

Rationale

Ensuring that /var is mounted on its own partition enables the setting of more restrictive mount options. This helps protect system services such as daemons or other programs which use it. It is not uncommon for the /var directory to contain world-writable directories installed by other software packages.

Ensure /var/log Located On Separate Partitionxccdf_org.ssgproject.content_rule_partition_for_var_log low

Ensure /var/log Located On Separate Partition

Rule IDxccdf_org.ssgproject.content_rule_partition_for_var_log
Result
pass
Time2016-07-11T14:18:34
Severitylow
Identifiers and References

identifiers: 

references:  AU-9, SC-32, http://iase.disa.mil/stigs/cci/Pages/index.aspx, 1.1.7, Test attestation on 20120928 by MM

Description

System logs are stored in the /var/log directory. Ensure that it has its own partition or logical volume at installation time, or migrate it using LVM.

Rationale

Placing /var/log in its own partition enables better separation between log files and other files in /var/.

Ensure /var/log/audit Located On Separate Partitionxccdf_org.ssgproject.content_rule_partition_for_var_log_audit low

Ensure /var/log/audit Located On Separate Partition

Rule IDxccdf_org.ssgproject.content_rule_partition_for_var_log_audit
Result
pass
Time2016-07-11T14:18:34
Severitylow
Identifiers and References

identifiers: 

references:  AU-4, AU-9, SC-32(1), 366, 1.1.8, SRG-OS-000480-GPOS-00227, RHEL-07-021260, Test attestation on 20120928 by MM

Description

Audit logs are stored in the /var/log/audit directory. Ensure that it has its own partition or logical volume at installation time, or migrate it later using LVM. Make absolutely certain that it is large enough to store all audit logs that will be created by the auditing daemon.

Rationale

Placing /var/log/audit in its own partition enables better separation between audit files and other files, and helps ensure that auditing cannot be halted due to the partition running out of space.

Ensure /home Located On Separate Partitionxccdf_org.ssgproject.content_rule_partition_for_home low

Ensure /home Located On Separate Partition

Rule IDxccdf_org.ssgproject.content_rule_partition_for_home
Result
pass
Time2016-07-11T14:18:34
Severitylow
Identifiers and References

identifiers: 

references:  SC-32(1), 366, 1208, 1.1.9, SRG-OS-000480-GPOS-00227, RHEL-07-021240, Test attestation on 20120928 by MM

Description

If user home directories will be stored locally, create a separate partition for /home at installation time (or migrate it later using LVM). If /home will be mounted from another system such as an NFS server, then creating a separate partition is not necessary at installation time, and the mountpoint can instead be configured later.

Rationale

Ensuring that /home is mounted on its own partition enables the setting of more restrictive mount options, and also helps ensure that users cannot trivially fill partitions used for log or audit data storage.

Encrypt Partitionsxccdf_org.ssgproject.content_rule_encrypt_partitions medium

Encrypt Partitions

Rule IDxccdf_org.ssgproject.content_rule_encrypt_partitions
Result
notchecked
Time2016-07-11T14:18:34
Severitymedium
Identifiers and References

identifiers: 

references:  SC-13, SC-28(1), 1199, 2476, SRG-OS-000405-GPOS-00184, SRG-OS-000185-GPOS-00079, RHEL-07-020170

Description

Red Hat Enterprise Linux 7 natively supports partition encryption through the Linux Unified Key Setup-on-disk-format (LUKS) technology. The easiest way to encrypt a partition is during installation time.

For manual installations, select the Encrypt checkbox during partition creation to encrypt the partition. When this option is selected the system will prompt for a passphrase to use in decrypting the partition. The passphrase will subsequently need to be entered manually every time the system boots.

For automated/unattended installations, it is possible to use Kickstart by adding the --encrypted and --passphrase= options to the definition of each partition to be encrypted. For example, the following line would encrypt the root partition:

part / --fstype=ext4 --size=100 --onpart=hda1 --encrypted --passphrase=PASSPHRASE
Any PASSPHRASE is stored in the Kickstart in plaintext, and the Kickstart must then be protected accordingly. Omitting the --passphrase= option from the partition definition will cause the installer to pause and interactively ask for the passphrase during installation.

Detailed information on encrypting partitions using LUKS can be found on the Red Hat Documentation web site:
https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/7/html/Security_Guide/sec-Encryption.html

Rationale

The risk of a system's physical compromise, particularly mobile systems such as laptops, places its data at risk of compromise. Encrypting this data mitigates the risk of its loss if the system is lost.

Evaluation messages
info 
No candidate or applicable check found.
Ensure Red Hat GPG Key Installedxccdf_org.ssgproject.content_rule_ensure_redhat_gpgkey_installed high

Ensure Red Hat GPG Key Installed

Rule IDxccdf_org.ssgproject.content_rule_ensure_redhat_gpgkey_installed
Result
pass
Time2016-07-11T14:18:35
Severityhigh
Identifiers and References

identifiers: 

references:  CM-5(3), SI-7, MA-1(b), 1749, 366, Req-6.2, 1.2.2, Test attestation on 20150407 by sdw

Description

To ensure the system can cryptographically verify base software packages come from Red Hat (and to connect to the Red Hat Network to receive them), the Red Hat GPG key must properly be installed. To install the Red Hat GPG key, run:

$ sudo rhn_register
If the system is not connected to the Internet or an RHN Satellite, then install the Red Hat GPG key from trusted media such as the Red Hat installation CD-ROM or DVD. Assuming the disc is mounted in /media/cdrom, use the following command as the root user to import it into the keyring:
$ sudo rpm --import /media/cdrom/RPM-GPG-KEY

Rationale

Changes to software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor. The Red Hat GPG key is necessary to cryptographically verify packages are from Red Hat.

Ensure gpgcheck Enabled In Main Yum Configurationxccdf_org.ssgproject.content_rule_ensure_gpgcheck_globally_activated high

Ensure gpgcheck Enabled In Main Yum Configuration

Rule IDxccdf_org.ssgproject.content_rule_ensure_gpgcheck_globally_activated
Result
pass
Time2016-07-11T14:18:35
Severityhigh
Identifiers and References

identifiers: 

references:  CM-5(3), SI-7, MA-1(b), 1749, SRG-OS-000366-GPOS-00153, RHEL-07-020150, Req-6.2, 1.2.3, Test attestation on 20150407 by sdw

Description

The gpgcheck option controls whether RPM packages' signatures are always checked prior to installation. To configure yum to check package signatures before installing them, ensure the following line appears in /etc/yum.conf in the [main] section:

gpgcheck=1

Rationale

Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor.
Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.
Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA).

Ensure gpgcheck Enabled For All Yum Package Repositoriesxccdf_org.ssgproject.content_rule_ensure_gpgcheck_never_disabled high

Ensure gpgcheck Enabled For All Yum Package Repositories

Rule IDxccdf_org.ssgproject.content_rule_ensure_gpgcheck_never_disabled
Result
pass
Time2016-07-11T14:18:35
Severityhigh
Identifiers and References

identifiers: 

references:  CM-5(3), SI-7, MA-1(b), 1749, 366, Req-6.2, Test attestation on 20150407 by sdw

Description

To ensure signature checking is not disabled for any repos, remove any lines from files in /etc/yum.repos.d of the form:

gpgcheck=0

Rationale

Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. Certificates used to verify the software must be from an approved Certificate Authority (CA).

Ensure Software Patches Installedxccdf_org.ssgproject.content_rule_security_patches_up_to_date high

Ensure Software Patches Installed

Rule IDxccdf_org.ssgproject.content_rule_security_patches_up_to_date
Result
notchecked
Time2016-07-11T14:18:35
Severityhigh
Identifiers and References

identifiers: 

references:  SI-2, MA-1(b), http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-6.2, 1.7, Test attestation on 20120928 by MM

Description

If the system is joined to the Red Hat Network, a Red Hat Satellite Server, or a yum server, run the following command to install updates:

$ sudo yum update
If the system is not configured to use one of these sources, updates (in the form of RPM packages) can be manually downloaded from the Red Hat Network and installed using rpm.

Rationale

Installing software updates is a fundamental mitigation against the exploitation of publicly-known vulnerabilities.

Evaluation messages
info 
None of the check-content-ref elements was resolvable.
Ensure YUM Removes Previous Package Versionsxccdf_org.ssgproject.content_rule_clean_components_post_updating low

Ensure YUM Removes Previous Package Versions

Rule IDxccdf_org.ssgproject.content_rule_clean_components_post_updating
Result
pass
Time2016-07-11T14:18:35
Severitylow
Identifiers and References

identifiers: 

references:  SI-2(6), 2617, SRG-OS-000437-GPOS-00194, RHEL-07-020200

Description

Yum should be configured to remove previous software components after previous versions have been installed. To configure yum to remove the previous software components after updating, set the clean_requirements_on_remove to 1 in /etc/yum.conf.

Rationale

Previous versions of software components that are not removed from the information system after updates have been installed may be exploited by some adversaries.

Ensure gpgcheck Enabled for Local Packagesxccdf_org.ssgproject.content_rule_ensure_gpgcheck_local_packages high

Ensure gpgcheck Enabled for Local Packages

Rule IDxccdf_org.ssgproject.content_rule_ensure_gpgcheck_local_packages
Result
pass
Time2016-07-11T14:18:35
Severityhigh
Identifiers and References

identifiers: 

references:  CM-5(3), 1749, SRG-OS-000366-GPOS-00153, RHEL-07-020151

Description

Yum should be configured to verify the signature(s) of local packages prior to installation. To configure yum to verify signatures of local packages, set the localpkg_gpgcheck to 1 in /etc/yum.conf.

Rationale

Changes to any software components can have significant effects to the overall security of the operating system. This requirement ensures the software has not been tampered and has been provided by a trusted vendor.

Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization.

Install AIDExccdf_org.ssgproject.content_rule_package_aide_installed medium

Install AIDE

Rule IDxccdf_org.ssgproject.content_rule_package_aide_installed
Result
pass
Time2016-07-11T14:18:35
Severitymedium
Identifiers and References

identifiers: 

references:  CM-3(d), CM-3(e), CM-6(d), CM-6(3), SC-28, SI-7, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-11.5, 1.3.1, Test attestation on 20121024 by DS

Description

Install the AIDE package with the command:

$ sudo yum install aide

Rationale

The AIDE package must be installed if it is to be available for integrity checking.

Build and Test AIDE Databasexccdf_org.ssgproject.content_rule_aide_build_database medium

Build and Test AIDE Database

Rule IDxccdf_org.ssgproject.content_rule_aide_build_database
Result
pass
Time2016-07-11T14:18:35
Severitymedium
Identifiers and References

identifiers: 

references:  CM-3(d), CM-3(e), CM-6(d), CM-6(3), SC-28, SI-7, Req-11.5

Description

Run the following command to generate a new database:

$ sudo /usr/sbin/aide --init
By default, the database will be written to the file /var/lib/aide/aide.db.new.gz. Storing the database, the configuration file /etc/aide.conf, and the binary /usr/sbin/aide (or hashes of these files), in a secure location (such as on read-only media) provides additional assurance about their integrity. The newly-generated database can be installed as follows:
$ sudo cp /var/lib/aide/aide.db.new.gz /var/lib/aide/aide.db.gz
To initiate a manual check, run the following command:
$ sudo /usr/sbin/aide --check
If this check produces any unexpected output, investigate.

Rationale

For AIDE to be effective, an initial database of "known-good" information about files must be captured and it should be able to be verified against the installed files.

Configure Periodic Execution of AIDExccdf_org.ssgproject.content_rule_aide_periodic_cron_checking medium

Configure Periodic Execution of AIDE

Rule IDxccdf_org.ssgproject.content_rule_aide_periodic_cron_checking
Result
pass
Time2016-07-11T14:18:35
Severitymedium
Identifiers and References

identifiers: 

references:  CM-3(d), CM-3(e), CM-6(d), CM-6(3), SC-28, SI-7, 374, 416, 1069, 1263, 1297, 1589, Req-11.5, 1.3.1

Description

To implement a daily execution of AIDE at 4:05am using cron, add the following line to /etc/crontab:

05 4 * * * root /usr/sbin/aide --check
AIDE can be executed periodically through other means; this is merely one example.

Rationale

By default, AIDE does not install itself for periodic execution. Periodically running AIDE is necessary to reveal unexpected changes in installed files.

Verify and Correct File Permissions with RPMxccdf_org.ssgproject.content_rule_rpm_verify_permissions high

Verify and Correct File Permissions with RPM

Rule IDxccdf_org.ssgproject.content_rule_rpm_verify_permissions
Result
error
Time2016-07-11T14:23:50
Severityhigh
Identifiers and References

identifiers: 

references:  AC-6, CM-6(d), CM-6(3), 1493, 1494, 1495, Req-11.5, 1.2.6, 6.1.3, 6.1.4, 6.1.5, 6.1.6, 6.1.7, 6.1.8, 6.1.9, 6.2.3, RHEL-07-010010

Description

Discretionary access control is weakened if a user or group has access permissions to system files and directories greater than the default. The RPM package management system can check file access permissions of installed software packages, including many that are important to system security. Verify that the file permissions, ownership, and gruop membership of system files and commands match vendor values. Check the file permissions, ownership, and group membership with the following command:

$ sudo rpm -Va | grep '^.M'
Output indicates files that do not match vendor defaults. After locating a file with incorrect permissions, run the following command to determine which package owns it:
$ rpm -qf FILENAME
Next, run the following command to reset its permissions to the correct values:
$ sudo rpm --setperms PACKAGENAME

Rationale

Permissions on system binaries and configuration files that are too generous could allow an unauthorized user to gain privileges that they should not have. The permissions set by the vendor should be maintained. Any deviations from this baseline should be investigated.

Warnings
warning  Note: Due to a bug in the gdm package, the RPM verify command may continue to fail even after file permissions have been correctly set on /var/log/gdm. This is being tracked in Red Hat Bugzilla #1275532.
Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:

# Declare array to hold list of RPM packages we need to correct permissions for
declare -a SETPERMS_RPM_LIST

# Create a list of files on the system having permissions different from what
# is expected by the RPM database
FILES_WITH_INCORRECT_PERMS=($(rpm -Va --nofiledigest | grep '^.M'))

# For each file path from that list:
# * Determine the RPM package the file path is shipped by,
# * Include it into SETPERMS_RPM_LIST array

for FILE_PATH in "${FILES_WITH_INCORRECT_PERMS[@]}"
do
	RPM_PACKAGE=$(rpm -qf "$FILE_PATH")
	SETPERMS_RPM_LIST=("${SETPERMS_RPM_LIST[@]}" "$RPM_PACKAGE")
done

# Remove duplicate mention of same RPM in $SETPERMS_RPM_LIST (if any)
SETPERMS_RPM_LIST=( $(echo "${SETPERMS_RPM_LIST[@]}" | sort -n | uniq) )

# For each of the RPM packages left in the list -- reset its permissions to the
# correct values
for RPM_PACKAGE in "${SETPERMS_RPM_LIST[@]}"
do
	rpm --setperms "${RPM_PACKAGE}"
done
Verify File Hashes with RPMxccdf_org.ssgproject.content_rule_rpm_verify_hashes high

Verify File Hashes with RPM

Rule IDxccdf_org.ssgproject.content_rule_rpm_verify_hashes
Result
pass
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

references:  CM-6(d), CM-6(3), SI-7, 1496, Req-11.5, 1.2.6, RHEL-07-010020

Description

Without cryptographic integrity protections, system executables and files can be altered by unauthorized users without detection. The RPM package management system can check the hashes of installed software packages, including many that are important to system security. To verify that the cryptographic hash of system files and commands match vendor values, run the following command to list which files on the system have hashes that differ from what is expected by the RPM database:

$ rpm -Va | grep '^..5'
A "c" in the second column indicates that a file is a configuration file, which may appropriately be expected to change. If the file was not expected to change, investigate the cause of the change using audit logs or other means. The package can then be reinstalled to restore the file. Run the following command to determine which package owns the file:
$ rpm -qf FILENAME
The package can be reinstalled from a yum repository using the command:
$ sudo yum reinstall PACKAGENAME
Alternatively, the package can be reinstalled from trusted media using the command:
$ sudo rpm -Uvh PACKAGENAME

Rationale

The hashes of important files like system executables should match the information given by the RPM database. Executables with erroneous hashes could be a sign of nefarious activity on the system.

Install Intrusion Detection Softwarexccdf_org.ssgproject.content_rule_install_hids high

Install Intrusion Detection Software

Rule IDxccdf_org.ssgproject.content_rule_install_hids
Result
notselected
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

references:  SC-7, 1263, Req-11.4

Description

The base Red Hat platform already includes a sophisticated auditing system that can detect intruder activity, as well as SELinux, which provides host-based intrusion prevention capabilities by confining privileged programs and user sessions which may become compromised.

Rationale

Host-based intrusion detection tools provide a system-level defense when an intruder gains access to a system or network.

Warnings
warning  Note in DoD environments, supplemental intrusion detection tools, such as the McAfee Host-based Security System, are available to integrate with existing infrastructure. When these supplemental tools interfere with proper functioning of SELinux, SELinux takes precedence.
Install Virus Scanning Softwarexccdf_org.ssgproject.content_rule_install_antivirus low

Install Virus Scanning Software

Rule IDxccdf_org.ssgproject.content_rule_install_antivirus
Result
notselected
Time2016-07-11T14:19:20
Severitylow
Identifiers and References

identifiers: 

references:  SC-28, SI-3, 1239, 1668

Description

Install virus scanning software, which uses signatures to search for the presence of viruses on the filesystem. Ensure virus definition files are no older than 7 days, or their last release. Configure the virus scanning software to perform scans dynamically on all accessed files. If this is not possible, configure the system to scan all altered files on the system on a daily basis. If the system processes inbound SMTP mail, configure the virus scanner to scan all received mail.

Rationale

Virus scanning software can be used to detect if a system has been compromised by computer viruses, as well as to limit their spread to other systems.

Install McAfee Host-Based Intrusion Detection Software (HBSS)xccdf_org.ssgproject.content_rule_install_mcafee_hbss medium

Install McAfee Host-Based Intrusion Detection Software (HBSS)

Rule IDxccdf_org.ssgproject.content_rule_install_mcafee_hbss
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  SC-7, SI-4(1).1, 366, 1263, Req-11.4, STG-OS-000480-GPOS-00227, 030790

Description

Install the McAfee Host-based Security System (HBSS) application.

Rationale

Without a host-based intrusion detection tool, there is no system-level defense when an intruder gains access to a system or network. Additionally, a host-based intrusion prevention tool can provide methods to immediately lock out detected intrusion attempts.

Install McAfee Virus Scanning Softwarexccdf_org.ssgproject.content_rule_install_mcafee_antivirus high

Install McAfee Virus Scanning Software

Rule IDxccdf_org.ssgproject.content_rule_install_mcafee_antivirus
Result
notselected
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

references:  SC-28, SI-3, SI-3(1)(ii), 366, 1239, 1668, SRG-OS-000480-GPOS-00227, RHEL-07-030810

Description

Install McAfee VirusScan Enterprise for Linux antivirus software which is provided for DoD systems and uses signatures to search for the presence of viruses on the filesystem.

Rationale

Virus scanning software can be used to detect if a system has been compromised by computer viruses, as well as to limit their spread to other systems.

Enable nails Servicexccdf_org.ssgproject.content_rule_service_nails_enabled medium

Enable nails Service

Rule IDxccdf_org.ssgproject.content_rule_service_nails_enabled
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  SC-28, SI-3, SI-3(1)(ii), 366, 1239, 1668, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

The nails service is used to run McAfee VirusScan Enterprise for Linux and McAfee Host-based Security System (HBSS) services. The nails service can be enabled with the following command:

$ sudo systemctl enable nails.service

Rationale

Virus scanning software can be used to detect if a system has been compromised by computer viruses, as well as to limit their spread to other systems.

Virus Scanning Software Definitions Are Updatedxccdf_org.ssgproject.content_rule_mcafee_antivirus_definitions_updated medium

Virus Scanning Software Definitions Are Updated

Rule IDxccdf_org.ssgproject.content_rule_mcafee_antivirus_definitions_updated
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  SC-28, SI-3, SI-3(1)(ii), 366, 1239, 1668, SRG-OS-000480-GPOS-00227, RHEL-07-030820

Description

Ensure virus definition files are no older than 7 days or their last release.

Rationale

Virus scanning software can be used to detect if a system has been compromised by computer viruses, as well as to limit their spread to other systems.

Install the dracut-fips Packagexccdf_org.ssgproject.content_rule_package_dracut-fips_installed medium

Install the dracut-fips Package

Rule IDxccdf_org.ssgproject.content_rule_package_dracut-fips_installed
Result
fail
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(2), 68, 2450, RHEL-07-TBD, SRG-OS-000033-GPOS-00014, SRG-OS-000396-GPOS-00176, SRG-OS-000478-GPOS-00223

Description

To enable FIPS, the system requires that the dracut-fips package be installed. The dracut-fips package can be installed with the following command:

$ sudo yum install dracut-fips

Rationale

Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The operating system must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated.

Enable FIPS Mode in GRUB2xccdf_org.ssgproject.content_rule_grub2_enable_fips_mode medium

Enable FIPS Mode in GRUB2

Rule IDxccdf_org.ssgproject.content_rule_grub2_enable_fips_mode
Result
error
Time2016-07-11T14:24:55
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(2), 68, 2450, RHEL-07-021280, SRG-OS-000033-GPOS-00014, SRG-OS-000396-GPOS-00176, SRG-OS-000478-GPOS-00223

Description

To ensure FIPS mode is enabled, rebuild initramfs by running the following command:

dracut -f
After the dracut command has been run, add the argument fips=1 to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:
GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=VolGroup/LogVol06 rd.lvm.lv=VolGroup/lv_swap rhgb quiet rd.shell=0 fips=1"
Finally, rebuild the grub.cfg file by using the
grub2-mkconfig -o
command as follows:
  • On BIOS-based machines, issue the following command as root:
    ~]# grub2-mkconfig -o /boot/grub2/grub.cfg
  • On UEFI-based machines, issue the following command as root:
    ~]# grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg

Rationale

Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The operating system must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated.

Warnings
warning  Running
dracut -f
will overwrite the existing initramfs file.
warning  The system needs to be rebooted for these changes to take effect.
warning  The ability to enable FIPS does not denote FIPS compliancy or certification. Red Hat, Inc. and Red Hat Enterprise Linux are respectively FIPS certified and compliant. Community projects such as CentOS, Scientific Linux, etc. do not necessarily meet FIPS certification and compliancy. Therefore, non-certified vendors and/or projects do not meet this requirement even if technically feasible.

See http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/1401vend.htm for a list of FIPS certified vendors.
Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:
sed -i 's/PRELINKING=yes/PRELINKING=no/g' /etc/sysconfig/prelink
prelink -u -a
dracut -f
if [ -e /sys/firmware/efi ]; then
	BOOT=`df /boot/efi | tail -1 | awk '{print $1 }'`
else
	BOOT=`df /boot | tail -1 | awk '{ print $1 }'`
fi
/sbin/grubby --update-kernel=ALL --args="boot=${BOOT} fips=1"
The Installed Operating System Is Vendor Supported and Certifiedxccdf_org.ssgproject.content_rule_installed_OS_is_certified high

The Installed Operating System Is Vendor Supported and Certified

Rule IDxccdf_org.ssgproject.content_rule_installed_OS_is_certified
Result
notselected
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

references:  SI-2(c), 366, RHEL-07-020240, SRG-OS-000480-GPOS-00227

Description

The installed operating system must be maintained and certified by a vendor. Red Hat Enterprise Linux is supported by Red Hat, Inc. As the Red Hat Enterprise Linux vendor, Red Hat, Inc. is responsible for providing security patches as well as meeting and maintaining goverment certifications and standards.

Rationale

An operating system is considered "supported" if the vendor continues to provide security patches for the product as well as maintain government certification requirements. With an unsupported release, it will not be possible to resolve security issue discovered in the system software as well as meet government certifications.

Disable the GNOME3 Login User Listxccdf_org.ssgproject.content_rule_dconf_gnome_disable_user_list medium

Disable the GNOME3 Login User List

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_user_list
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  AC-23

Description

In the default graphical environment, users logging directly into the system are greeted with a login screen that displays all known users. This functionality should be disabled by setting disable-user-list to true.

To disable, add or edit disable-user-list to /etc/dconf/db/gdm.d/00-security-settings. For example:

[org/gnome/login-screen]
disable-user-list=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/disable-user-list
After the settings have been set, run dconf update.

Rationale

Leaving the user list enabled is a security risk since it allows anyone with physical access to the system to quickly enumerate known user accounts without logging in.

Disable the GNOME3 Login Restart and Shutdown Buttonsxccdf_org.ssgproject.content_rule_dconf_gnome_disable_restart_shutdown high

Disable the GNOME3 Login Restart and Shutdown Buttons

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_restart_shutdown
Result
notselected
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

In the default graphical environment, users logging directly into the system are greeted with a login screen that allows any user, known or unknown, the ability the ability to shutdown or restart the system. This functionality should be disabled by setting disable-restart-buttons to true.

To disable, add or edit disable-restart-buttons to /etc/dconf/db/gdm.d/00-security-settings. For example:

[org/gnome/login-screen]
disable-restart-buttons=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/disable-restart-buttons
After the settings have been set, run dconf update.

Rationale

A user who is at the console can reboot the system at the login screen. If restart or shutdown buttons are pressed at the login screen, this can create the risk of short-term loss of availability of systems due to reboot.

Enable the GNOME3 Login Smartcard Authenticationxccdf_org.ssgproject.content_rule_dconf_gnome_enable_smartcard_auth medium

Enable the GNOME3 Login Smartcard Authentication

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_enable_smartcard_auth
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  765, 766, 767, 768, 771, 772, 884, Req-8.3

Description

In the default graphical environment, smart card authentication can be enabled on the login screen by setting enable-smartcard-authentication to true.

To enable, add or edit enable-smartcard-authentication to /etc/dconf/db/gdm.d/00-security-settings. For example:

[org/gnome/login-screen]
enable-smartcard-authentication=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/login-screen/enable-smartcard-authentication
After the settings have been set, run dconf update.

Rationale

Smart card login provides two-factor authentication stronger than that provided by a username and password combination. Smart cards leverage PKI (public key infrastructure) in order to provide and verify credentials.

Set GNOME3 Screensaver Inactivity Timeoutxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_delay medium

Set GNOME3 Screensaver Inactivity Timeout

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_delay
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  AC-11(a), 57, Req-8.1.8, SRG-OS-000029-GPOS-00010, RHEL-07-010070

Description

The idle time-out value for inactivity in the GNOME3 desktop is configured via the idle-delay setting must be set under an appropriate configuration file(s) in the /etc/dconf/db/local.d directory and locked in /etc/dconf/db/local.d/locks directory to prevent user modification.
For example, to configure the system for a 15 minute delay, add the following to /etc/dconf/db/local.d/00-security-settings:

[org/gnome/desktop/session]
idle-delay=900
Once the setting has been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/session/idle-delay
After the settings have been set, run dconf update.

Rationale

A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME3 can be configured to identify when a user's session has idled and take action to initiate a session lock.

Enable GNOME3 Screensaver Idle Activationxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_activation_enabled medium

Enable GNOME3 Screensaver Idle Activation

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_idle_activation_enabled
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  AC-11(a), 57, SRG-OS-000029-GPOS-00010, RHEL-07-010073, Req-8.1.8

Description

To activate the screensaver in the GNOME3 desktop after a period of inactivity, add or set idle-activation-enabled to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/desktop/screensaver]
idle_activation_enabled=true
Once the setting has been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/idle-activation-enabled
After the settings have been set, run dconf update.

Rationale

A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operating system session prior to vacating the vicinity, GNOME desktops can be configured to identify when a user's session has idled and take action to initiate the session lock. Enabling idle activation of the screensaver ensures the screensaver will be activated after the idle delay. Applications requiring continuous, real-time screen display (such as network management products) require the login session does not have administrator rights and the display station is located in a controlled-access area.

Enable GNOME3 Screensaver Lock After Idle Periodxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_enabled medium

Enable GNOME3 Screensaver Lock After Idle Period

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_lock_enabled
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  AC-11(b), 56, Req-8.1.8, SRG-OS-000028-GPOS-00009, OS-SRG-000030-GPOS-00011, RHEL-07-010060

Description

To activate locking of the screensaver in the GNOME3 desktop when it is activated, add or set lock-enabled to true and lock-delay to 0 in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/desktop/screensaver]
lock-enabled=true
lock-delay=0
Once the settings have been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/lock-enabled
/org/gnome/desktop/screensaver/lock-delay
After the settings have been set, run dconf update.

Rationale

A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to logout because of the temporary nature of the absense.

Implement Blank Screensaverxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_mode_blank low

Implement Blank Screensaver

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_screensaver_mode_blank
Result
notselected
Time2016-07-11T14:19:20
Severitylow
Identifiers and References

identifiers: 

references:  AC-11(b), 60, Req-8.1.8

Description

To set the screensaver mode in the GNOME3 desktop to a blank screen, add or set picture-uri to '' in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/desktop/screensaver]
picture-uri=''
Once the settings have been added, add a lock to /etc/dconf/db/gdm.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/screensaver/picture-uri
After the settings have been set, run dconf update.

Rationale

Setting the screensaver mode to blank-only conceals the contents of the display from passersby.

Disable Ctrl-Alt-Del Reboot Key Sequence in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_disable_ctrlaltdel_reboot high

Disable Ctrl-Alt-Del Reboot Key Sequence in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_ctrlaltdel_reboot
Result
notselected
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

By default, GNOME will reboot the system if the Ctrl-Alt-Del key sequence is pressed.
To configure the system to ignore the Ctrl-Alt-Del key sequence from the Graphical User Interface (GUI) instead of rebooting the system, add or set logout to '' in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/settings-daemon/plugins/media-keys]
logout=''
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/settings-daemon/plugins/media-keys/logout
After the settings have been set, run dconf update.

Rationale

A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot.

Disable User Administration in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_disable_user_admin high

Disable User Administration in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_user_admin
Result
notselected
Time2016-07-11T14:19:20
Severityhigh
Identifiers and References

identifiers: 

Description

By default, GNOME will allow all users to have some administratrion capability. This should be disabled so that non-administrative users are not making configuration changes. To configure the system to disable user administration capability in the Graphical User Interface (GUI), add or set user-administration-disabled to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/desktop/lockdown]
user-administration-disabled=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/lockdown/user-administration-disabled
After the settings have been set, run dconf update.

Rationale

Allowing all users to have some administratrive capabilities to the system through the Graphical User Interface (GUI) when they would not have them otherwise could allow unintended configuration changes as well as a nefarious user the capability to make system changes such as adding new accounts, etc.

Disable Power Settings in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_disable_power_settings medium

Disable Power Settings in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_power_settings
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

Description

By default, GNOME enables a power profile designed for mobile devices with battery usage. While useful for mobile devices, this setting should be disabled for all other systems. To configure the system to disable the power setting, add or set active to false in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/settings-daemon/plugins/power]
active=false
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/settings-daemon/plugins/power
After the settings have been set, run dconf update.

Rationale

Power settings should not be enabled on systems that are not mobile devices. Enabling power settings on non-mobile devices could have unintended processing consequences on standard systems.

Disable Geolocation in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_disable_geolocation medium

Disable Geolocation in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_geolocation
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

Description

GNOME allows the clock and applications to track and access location information. This setting should be disabled as applications should not track system location. To configure the system to disable location tracking, add or set enabled to false in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/system/location]
enabled=false
To configure the clock to disable location tracking, add or set geolocation to false in /etc/dconf/db/local.d/00-security-settings. For example:
[org/gnome/clocks]
geolocation=false
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/system/location/enabled
/org/gnome/clocks/geolocation
After the settings have been set, run dconf update.

Rationale

Power settings should not be enabled on systems that are not mobile devices. Enabling power settings on non-mobile devices could have unintended processing consequences on standard systems.

Disable WIFI Network Connection Creation in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_disable_wifi_create medium

Disable WIFI Network Connection Creation in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_wifi_create
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

Description

GNOME allows users to create ad-hoc wireless connections through the NetworkManager applet. Wireless connections should be disabled by adding or setting disable-wifi-create to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/nm-applet]
disable-wifi-create=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/nm-applet/disable-wifi-create
After the settings have been set, run dconf update.

Rationale

Wireless network connections should not be allowed to be configured by general users on a given system as it could open the system to backdoor attacks.

Disable WIFI Network Notification in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_disable_wifi_notification medium

Disable WIFI Network Notification in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_wifi_notification
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

Description

By default, GNOME disables WIFI notification. This should be permanently set so that users do not connect to a wireless network when the system finds one. While useful for mobile devices, this setting should be disabled for all other systems. To configure the system to disable the WIFI notication, add or set suppress-wireless-networks-available to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/nm-applet]
suppress-wireless-networks-available=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/nm-applet/suppress-wireless-networks-available
After the settings have been set, run dconf update.

Rationale

Wireless network connections should not be allowed to be configured by general users on a given system as it could open the system to backdoor attacks.

Require Credential Prompting for Remote Access in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_remote_access_credential_prompt medium

Require Credential Prompting for Remote Access in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_remote_access_credential_prompt
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

Description

By default, GNOME does not require credentials when using Vino for remote access. To configure the system to require remote credentials, add or set authentication-methods to ['vnc'] in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/Vino]
authentication-methods=['vnc']
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/Vino/authentication-methods
After the settings have been set, run dconf update.

Rationale

Username and password prompting is required for remote access. Otherwise, non-authorized and nefarious users can access the system freely.

Require Encryption for Remote Access in GNOME3xccdf_org.ssgproject.content_rule_dconf_gnome_remote_access_encryption medium

Require Encryption for Remote Access in GNOME3

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_remote_access_encryption
Result
notselected
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  CM-2(1)(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

By default, GNOME requires encryption when using Vino for remote access. To prevent remote access encryption from being disabled, add or set require-encryption to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/Vino]
require-encryption=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/Vino/require-encryption
After the settings have been set, run dconf update.

Rationale

Open X displays allow an attacker to capture keystrokes and to execute commands remotely.

Disable GNOME3 Automountingxccdf_org.ssgproject.content_rule_dconf_gnome_disable_automount low

Disable GNOME3 Automounting

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_automount
Result
notselected
Time2016-07-11T14:19:20
Severitylow
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e)

Description

The system's default desktop environment, GNOME3, will mount devices and removable media (such as DVDs, CDs and USB flash drives) whenever they are inserted into the system. To disable automount and autorun within GNOME3, add or set automount to false, automount-open to false, and autorun-never to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/desktop/media-handling]
automount=false
automount-open=false
autorun-never=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/media-handling/automount
/org/gnome/desktop/media-handling/auto-open
/org/gnome/desktop/media-handling/autorun-never
After the settings have been set, run dconf update.

Rationale

Disabling automatic mounting in GNOME3 can prevent the introduction of malware via removable media. It will, however, also prevent desktop users from legitimate use of removable media.

Disable All GNOME3 Thumbnailersxccdf_org.ssgproject.content_rule_dconf_gnome_disable_thumbnailers low

Disable All GNOME3 Thumbnailers

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_disable_thumbnailers
Result
notselected
Time2016-07-11T14:19:20
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The system's default desktop environment, GNOME3, uses a number of different thumbnailer programs to generate thumbnails for any new or modified content in an opened folder. To disable the execution of these thumbnail applications, add or set disable-all to true in /etc/dconf/db/local.d/00-security-settings. For example:

[org/gnome/desktop/thumbnailers]
disable-all=true
Once the settings have been added, add a lock to /etc/dconf/db/local.d/locks/00-security-settings-lock to prevent user modification. For example:
/org/gnome/desktop/thumbnailers/disable-all
After the settings have been set, run dconf update. This effectively prevents an attacker from gaining access to a system through a flaw in GNOME3's Nautilus thumbnail creators.

Rationale

An attacker with knowledge of a flaw in a GNOME3 thumbnailer application could craft a malicious file to exploit this flaw. Assuming the attacker could place the malicious file on the local filesystem (via a web upload for example) and assuming a user browses the same location using Nautilus, the malicious file would exploit the thumbnailer with the potential for malicious code execution. It is best to disable these thumbnailer applications unless they are explicitly required.

Ensure NOPASSWD Is Not Used in Sudoxccdf_org.ssgproject.content_rule_sudo_remove_nopasswd medium

Ensure NOPASSWD Is Not Used in Sudo

Rule IDxccdf_org.ssgproject.content_rule_sudo_remove_nopasswd
Result
pass
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  IA-11, 2038, RHEL-07-01038, SRG-OS-000373-GPOS-00156, SRG-OS-000373-GPOS-00157, SRG-OS-000373-GPOS-00158

Description

The sudo NOPASSWD tag, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the NOPASSWD tag does not exist in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d.

Rationale

Without re-authentication, users may access resources or perform tasks for which they do not have authorization.

When operating systems provide the capability to escalate a functional capability, it is critical that the user re-authenticate.

Ensure !authenticate Is Not Used in Sudoxccdf_org.ssgproject.content_rule_sudo_remove_no_authenticate medium

Ensure !authenticate Is Not Used in Sudo

Rule IDxccdf_org.ssgproject.content_rule_sudo_remove_no_authenticate
Result
pass
Time2016-07-11T14:19:20
Severitymedium
Identifiers and References

identifiers: 

references:  IA-11, 2038, RHEL-07-, SRG-OS-000373-GPOS-00156, SRG-OS-000373-GPOS-00157, SRG-OS-000373-GPOS-00158

Description

The sudo !authenticate option, when specified, allows a user to execute commands using sudo without having to authenticate. This should be disabled by making sure that the !authenticate option does not exist in /etc/sudoers configuration file or any sudo configuration snippets in /etc/sudoers.d.

Rationale

Without re-authentication, users may access resources or perform tasks for which they do not have authorization.

When operating systems provide the capability to escalate a functional capability, it is critical that the user re-authenticate.

Add nodev Option to Non-Root Local Partitionsxccdf_org.ssgproject.content_rule_mount_option_nodev_nonroot_local_partitions low

Add nodev Option to Non-Root Local Partitions

Rule IDxccdf_org.ssgproject.content_rule_mount_option_nodev_nonroot_local_partitions
Result
fail
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.11

Description

The nodev mount option prevents files from being interpreted as character or block devices. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of any non-root local partitions.

Rationale

The nodev mount option prevents files from being interpreted as character or block devices. The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails, for which it is not advised to set nodev on these filesystems.

Add nodev Option to Removable Media Partitionsxccdf_org.ssgproject.content_rule_mount_option_nodev_removable_partitions low

Add nodev Option to Removable Media Partitions

Rule IDxccdf_org.ssgproject.content_rule_mount_option_nodev_removable_partitions
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), CM-7, MP-2

Description

The nodev mount option prevents files from being interpreted as character or block devices. Legitimate character and block devices should exist only in the /dev directory on the root partition or within chroot jails built for system services. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of any removable media partitions.

Rationale

The only legitimate location for device files is the /dev directory located on the root partition. An exception to this is chroot jails, and it is not advised to set nodev on partitions which contain their root filesystems.

Add noexec Option to Removable Media Partitionsxccdf_org.ssgproject.content_rule_mount_option_noexec_removable_partitions low

Add noexec Option to Removable Media Partitions

Rule IDxccdf_org.ssgproject.content_rule_mount_option_noexec_removable_partitions
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), CM-7, MP-2, 87, 1.1.12

Description

The noexec mount option prevents the direct execution of binaries on the mounted filesystem. Preventing the direct execution of binaries from removable media (such as a USB key) provides a defense against malicious software that may be present on such untrusted media. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of any removable media partitions.

Rationale

Allowing users to execute binaries from removable media such as USB keys exposes the system to potential compromise.

Add nosuid Option to Removable Media Partitionsxccdf_org.ssgproject.content_rule_mount_option_nosuid_removable_partitions low

Add nosuid Option to Removable Media Partitions

Rule IDxccdf_org.ssgproject.content_rule_mount_option_nosuid_removable_partitions
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), CM-7, MP-2, 1.1.13

Description

The nosuid mount option prevents set-user-identifier (SUID) and set-group-identifier (SGID) permissions from taking effect. These permissions allow users to execute binaries with the same permissions as the owner and group of the file respectively. Users should not be allowed to introduce SUID and SGID files into the system via partitions mounted from removeable media. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of any removable media partitions.

Rationale

The presence of SUID and SGID executables should be tightly controlled. Allowing users to introduce SUID or SGID binaries from partitions mounted off of removable media would allow them to introduce their own highly-privileged programs.

Add nodev Option to /tmpxccdf_org.ssgproject.content_rule_mount_option_tmp_nodev low

Add nodev Option to /tmp

Rule IDxccdf_org.ssgproject.content_rule_mount_option_tmp_nodev
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MP-2, 1.1.2

Description

The nodev mount option can be used to prevent device files from being created in /tmp. Legitimate character and block devices should not exist within temporary directories like /tmp. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /tmp.

Rationale

The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.

Add noexec Option to /tmpxccdf_org.ssgproject.content_rule_mount_option_tmp_noexec low

Add noexec Option to /tmp

Rule IDxccdf_org.ssgproject.content_rule_mount_option_tmp_noexec
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MP-2, 1.1.4

Description

The noexec mount option can be used to prevent binaries from being executed out of /tmp. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /tmp.

Rationale

Allowing users to execute binaries from world-writable directories such as /tmp should never be necessary in normal operation and can expose the system to potential compromise.

Add nosuid Option to /tmpxccdf_org.ssgproject.content_rule_mount_option_tmp_nosuid low

Add nosuid Option to /tmp

Rule IDxccdf_org.ssgproject.content_rule_mount_option_tmp_nosuid
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MP-2, 1.1.3

Description

The nosuid mount option can be used to prevent execution of setuid programs in /tmp. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /tmp.

Rationale

The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions.

Add nodev Option to /dev/shmxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nodev low

Add nodev Option to /dev/shm

Rule IDxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nodev
Result
notselected
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MP-2, 1.1.14

Description

The nodev mount option can be used to prevent creation of device files in /dev/shm. Legitimate character and block devices should not exist within temporary directories like /dev/shm. Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.

Rationale

The only legitimate location for device files is the /dev directory located on the root partition. The only exception to this is chroot jails.

Add noexec Option to /dev/shmxccdf_org.ssgproject.content_rule_mount_option_dev_shm_noexec low

Add noexec Option to /dev/shm

Rule IDxccdf_org.ssgproject.content_rule_mount_option_dev_shm_noexec
Result
notselected
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MP-2, 1.1.16

Description

The noexec mount option can be used to prevent binaries from being executed out of /dev/shm. It can be dangerous to allow the execution of binaries from world-writable temporary storage directories such as /dev/shm. Add the noexec option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.

Rationale

Allowing users to execute binaries from world-writable directories such as /dev/shm can expose the system to potential compromise.

Add nosuid Option to /dev/shmxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nosuid low

Add nosuid Option to /dev/shm

Rule IDxccdf_org.ssgproject.content_rule_mount_option_dev_shm_nosuid
Result
notselected
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MP-2, 1.1.14

Description

The nosuid mount option can be used to prevent execution of setuid programs in /dev/shm. The SUID and SGID permissions should not be required in these world-writable directories. Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of /dev/shm.

Rationale

The presence of SUID and SGID executables should be tightly controlled. Users should not be able to execute SUID or SGID binaries from temporary storage partitions.

Bind Mount /var/tmp To /tmpxccdf_org.ssgproject.content_rule_mount_option_var_tmp_bind low

Bind Mount /var/tmp To /tmp

Rule IDxccdf_org.ssgproject.content_rule_mount_option_var_tmp_bind
Result
error
Time2016-07-11T14:24:56
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.6

Description

The /var/tmp directory is a world-writable directory. Bind-mount it to /tmp in order to consolidate temporary storage into one location protected by the same techniques as /tmp. To do so, edit /etc/fstab and add the following line:

/tmp     /var/tmp     none     rw,nodev,noexec,nosuid,bind     0 0
See the mount(8) man page for further explanation of bind mounting.

Rationale

Having multiple locations for temporary storage is not required. Unless absolutely necessary to meet requirements, the storage location /var/tmp should be bind mounted to /tmp and thus share the same protections.

Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:
FSTAB=/etc/fstab
echo "/tmp     /var/tmp     none     rw,nodev,noexec,nosuid,bind     0 0" >> $FSTAB
Disable Modprobe Loading of USB Storage Driverxccdf_org.ssgproject.content_rule_kernel_module_usb-storage_disabled medium

Disable Modprobe Loading of USB Storage Driver

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_usb-storage_disabled
Result
notselected
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), IA-3, 366, 778, 1958, SRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-0016, SRG-OS-000480-GPOS-00227, RHEL-07-020160

Description

To prevent USB storage devices from being used, configure the kernel module loading system to prevent automatic loading of the USB storage driver. To configure the system to prevent the usb-storage kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install usb-storage /bin/true
This will prevent the modprobe program from loading the usb-storage module, but will not prevent an administrator (or another program) from using the insmod program to load the module manually.

Rationale

USB storage devices such as thumb drives can be used to introduce malicious software.

Disable Kernel Support for USB via Bootloader Configurationxccdf_org.ssgproject.content_rule_bootloader_nousb_argument low

Disable Kernel Support for USB via Bootloader Configuration

Rule IDxccdf_org.ssgproject.content_rule_bootloader_nousb_argument
Result
notselected
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), 1250

Description

All USB support can be disabled by adding the nousb argument to the kernel's boot loader configuration. To do so, append "nousb" to the kernel line in /etc/default/grub as shown:

kernel /vmlinuz-VERSION ro vga=ext root=/dev/VolGroup00/LogVol00 rhgb quiet nousb
WARNING: Disabling all kernel support for USB will cause problems for systems with USB-based keyboards, mice, or printers. This configuration is infeasible for systems which require USB devices, which is common.

Rationale

Disabling the USB subsystem within the Linux kernel at system boot will protect against potentially malicious USB devices, although it is only practical in specialized systems.

Disable Booting from USB Devices in Boot Firmwarexccdf_org.ssgproject.content_rule_bios_disable_usb_boot low

Disable Booting from USB Devices in Boot Firmware

Rule IDxccdf_org.ssgproject.content_rule_bios_disable_usb_boot
Result
notselected
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), 1250

Description

Configure the system boot firmware (historically called BIOS on PC systems) to disallow booting from USB drives.

Rationale

Booting a system from a USB device would allow an attacker to circumvent any security measures provided by the operating system. Attackers could mount partitions and modify the configuration of the OS.

Assign Password to Prevent Changes to Boot Firmware Configurationxccdf_org.ssgproject.content_rule_bios_assign_password low

Assign Password to Prevent Changes to Boot Firmware Configuration

Rule IDxccdf_org.ssgproject.content_rule_bios_assign_password
Result
notselected
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

Description

Assign a password to the system boot firmware (historically called BIOS on PC systems) to require a password for any configuration changes.

Rationale

Assigning a password to the system boot firmware prevents anyone with physical access from configuring the system to boot from local media and circumvent the operating system's access controls. For systems in physically secure locations, such as a data center or Sensitive Compartmented Information Facility (SCIF), this risk must be weighed against the risk of administrative personnel being unable to conduct recovery operations in a timely fashion.

Disable the Automounterxccdf_org.ssgproject.content_rule_service_autofs_disabled medium

Disable the Automounter

Rule IDxccdf_org.ssgproject.content_rule_service_autofs_disabled
Result
notselected
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-19(a), AC-19(d), AC-19(e), IA-3, 366, 778, 1958, SRG-OS-000114-GPOS-00059, SRG-OS-000378-GPOS-00163, SRG-OS-000480-GPOS-00227, RHEL-07-020160

Description

The autofs daemon mounts and unmounts filesystems, such as user home directories shared via NFS, on demand. In addition, autofs can be used to handle removable media, and the default configuration provides the cdrom device as /misc/cd. However, this method of providing access to removable media is not common, so autofs can almost always be disabled if NFS is not in use. Even if NFS is required, it may be possible to configure filesystem mounts statically by editing /etc/fstab rather than relying on the automounter.

The autofs service can be disabled with the following command:

$ sudo systemctl disable autofs.service

Rationale

Disabling the automounter permits the administrator to statically control filesystem mounting through /etc/fstab.

Disable Mounting of cramfsxccdf_org.ssgproject.content_rule_kernel_module_cramfs_disabled low

Disable Mounting of cramfs

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_cramfs_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.18

Description

To configure the system to prevent the cramfs kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install cramfs /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Disable Mounting of freevxfsxccdf_org.ssgproject.content_rule_kernel_module_freevxfs_disabled low

Disable Mounting of freevxfs

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_freevxfs_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.19

Description

To configure the system to prevent the freevxfs kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install freevxfs /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Disable Mounting of jffs2xccdf_org.ssgproject.content_rule_kernel_module_jffs2_disabled low

Disable Mounting of jffs2

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_jffs2_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.20

Description

To configure the system to prevent the jffs2 kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install jffs2 /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Disable Mounting of hfsxccdf_org.ssgproject.content_rule_kernel_module_hfs_disabled low

Disable Mounting of hfs

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_hfs_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.21

Description

To configure the system to prevent the hfs kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install hfs /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Disable Mounting of hfsplusxccdf_org.ssgproject.content_rule_kernel_module_hfsplus_disabled low

Disable Mounting of hfsplus

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_hfsplus_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.22

Description

To configure the system to prevent the hfsplus kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install hfsplus /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Disable Mounting of squashfsxccdf_org.ssgproject.content_rule_kernel_module_squashfs_disabled low

Disable Mounting of squashfs

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_squashfs_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.23

Description

To configure the system to prevent the squashfs kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install squashfs /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Disable Mounting of udfxccdf_org.ssgproject.content_rule_kernel_module_udf_disabled low

Disable Mounting of udf

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_udf_disabled
Result
pass
Time2016-07-11T14:19:21
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1.1.24

Description

To configure the system to prevent the udf kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install udf /bin/true
This effectively prevents usage of this uncommon filesystem.

Rationale

Linux kernel modules which implement filesystems that are not needed by the local system should be disabled.

Verify User Who Owns shadow Filexccdf_org.ssgproject.content_rule_userowner_shadow_file medium

Verify User Who Owns shadow File

Rule IDxccdf_org.ssgproject.content_rule_userowner_shadow_file
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the owner of /etc/shadow, run the command:

$ sudo chown root /etc/shadow

Rationale

The /etc/shadow file contains the list of local system accounts and stores password hashes. Protection of this file is critical for system security. Failure to give ownership of this file to root provides the designated owner with access to sensitive information which could weaken the system security posture.

Verify Group Who Owns shadow Filexccdf_org.ssgproject.content_rule_groupowner_shadow_file medium

Verify Group Who Owns shadow File

Rule IDxccdf_org.ssgproject.content_rule_groupowner_shadow_file
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the group owner of /etc/shadow, run the command:

$ sudo chgrp root /etc/shadow

Rationale

The /etc/shadow file stores password hashes. Protection of this file is critical for system security.

Verify Permissions on shadow Filexccdf_org.ssgproject.content_rule_file_permissions_etc_shadow medium

Verify Permissions on shadow File

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_etc_shadow
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the permissions of /etc/shadow, run the command:

$ sudo chmod 0000 /etc/shadow

Rationale

The /etc/shadow file contains the list of local system accounts and stores password hashes. Protection of this file is critical for system security. Failure to give ownership of this file to root provides the designated owner with access to sensitive information which could weaken the system security posture.

Verify User Who Owns group Filexccdf_org.ssgproject.content_rule_file_owner_etc_group medium

Verify User Who Owns group File

Rule IDxccdf_org.ssgproject.content_rule_file_owner_etc_group
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the owner of /etc/group, run the command:

$ sudo chown root /etc/group

Rationale

The /etc/group file contains information regarding groups that are configured on the system. Protection of this file is important for system security.

Verify Group Who Owns group Filexccdf_org.ssgproject.content_rule_file_groupowner_etc_group medium

Verify Group Who Owns group File

Rule IDxccdf_org.ssgproject.content_rule_file_groupowner_etc_group
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the group owner of /etc/group, run the command:

$ sudo chgrp root /etc/group

Rationale

The /etc/group file contains information regarding groups that are configured on the system. Protection of this file is important for system security.

Verify Permissions on group Filexccdf_org.ssgproject.content_rule_file_permissions_etc_group medium

Verify Permissions on group File

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_etc_group
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the permissions of /etc/group, run the command:

$ sudo chmod 644 /etc/group

Rationale

The /etc/group file contains information regarding groups that are configured on the system. Protection of this file is important for system security.

Verify User Who Owns gshadow Filexccdf_org.ssgproject.content_rule_file_owner_etc_gshadow medium

Verify User Who Owns gshadow File

Rule IDxccdf_org.ssgproject.content_rule_file_owner_etc_gshadow
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20121026 by DS

Description

To properly set the owner of /etc/gshadow, run the command:

$ sudo chown root /etc/gshadow

Rationale

The /etc/gshadow file contains group password hashes. Protection of this file is critical for system security.

Verify Group Who Owns gshadow Filexccdf_org.ssgproject.content_rule_file_groupowner_etc_gshadow medium

Verify Group Who Owns gshadow File

Rule IDxccdf_org.ssgproject.content_rule_file_groupowner_etc_gshadow
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20121026 by DS

Description

To properly set the group owner of /etc/gshadow, run the command:

$ sudo chgrp root /etc/gshadow

Rationale

The /etc/gshadow file contains group password hashes. Protection of this file is critical for system security.

Verify Permissions on gshadow Filexccdf_org.ssgproject.content_rule_file_permissions_etc_gshadow medium

Verify Permissions on gshadow File

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_etc_gshadow
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20121026 by DS

Description

To properly set the permissions of /etc/gshadow, run the command:

$ sudo chmod 0000 /etc/gshadow

Rationale

The /etc/gshadow file contains group password hashes. Protection of this file is critical for system security.

Verify User Who Owns passwd Filexccdf_org.ssgproject.content_rule_file_owner_etc_passwd medium

Verify User Who Owns passwd File

Rule IDxccdf_org.ssgproject.content_rule_file_owner_etc_passwd
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the owner of /etc/passwd, run the command:

$ sudo chown root /etc/passwd

Rationale

The /etc/passwd file contains information about the users that are configured on the system. Protection of this file is critical for system security.

Verify Group Who Owns passwd Filexccdf_org.ssgproject.content_rule_file_groupowner_etc_passwd medium

Verify Group Who Owns passwd File

Rule IDxccdf_org.ssgproject.content_rule_file_groupowner_etc_passwd
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the group owner of /etc/passwd, run the command:

$ sudo chgrp root /etc/passwd

Rationale

The /etc/passwd file contains information about the users that are configured on the system. Protection of this file is critical for system security.

Verify Permissions on passwd Filexccdf_org.ssgproject.content_rule_file_permissions_etc_passwd medium

Verify Permissions on passwd File

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_etc_passwd
Result
pass
Time2016-07-11T14:19:21
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.7.c, Test attestation on 20121026 by DS

Description

To properly set the permissions of /etc/passwd, run the command:

$ sudo chmod 0644 /etc/passwd

Rationale

If the /etc/passwd file is writable by a group-owner or the world the risk of its compromise is increased. The file contains the list of accounts on the system and associated information, and protection of this file is critical for system security.

Verify that Shared Library Files Have Restrictive Permissionsxccdf_org.ssgproject.content_rule_file_permissions_library_dirs medium

Verify that Shared Library Files Have Restrictive Permissions

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_library_dirs
Result
pass
Time2016-07-11T14:19:28
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20121026 by DS

Description

System-wide shared library files, which are linked to executables during process load time or run time, are stored in the following directories by default:

/lib
/lib64
/usr/lib
/usr/lib64
Kernel modules, which can be added to the kernel during runtime, are stored in /lib/modules. All files in these directories should not be group-writable or world-writable. If any file in these directories is found to be group-writable or world-writable, correct its permission with the following command:
$ sudo chmod go-w FILE

Rationale

Files from shared library directories are loaded into the address space of processes (including privileged ones) or of the kernel itself at runtime. Restrictive permissions are necessary to protect the integrity of the system.

Verify that Shared Library Files Have Root Ownershipxccdf_org.ssgproject.content_rule_file_ownership_library_dirs medium

Verify that Shared Library Files Have Root Ownership

Rule IDxccdf_org.ssgproject.content_rule_file_ownership_library_dirs
Result
pass
Time2016-07-11T14:19:28
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20130914 by swells

Description

System-wide shared library files, which are linked to executables during process load time or run time, are stored in the following directories by default:

/lib
/lib64
/usr/lib
/usr/lib64
Kernel modules, which can be added to the kernel during runtime, are also stored in /lib/modules. All files in these directories should be owned by the root user. If the directory, or any file in these directories, is found to be owned by a user other than root correct its ownership with the following command:
$ sudo chown root FILE

Rationale

Files from shared library directories are loaded into the address space of processes (including privileged ones) or of the kernel itself at runtime. Proper ownership is necessary to protect the integrity of the system.

Verify that System Executables Have Restrictive Permissionsxccdf_org.ssgproject.content_rule_file_permissions_binary_dirs medium

Verify that System Executables Have Restrictive Permissions

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_binary_dirs
Result
pass
Time2016-07-11T14:19:29
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx

Description

System executables are stored in the following directories by default:

/bin
/sbin
/usr/bin
/usr/libexec
/usr/local/bin
/usr/local/sbin
/usr/sbin
All files in these directories should not be group-writable or world-writable. If any file FILE in these directories is found to be group-writable or world-writable, correct its permission with the following command:
$ sudo chmod go-w FILE

Rationale

System binaries are executed by privileged users, as well as system services, and restrictive permissions are necessary to ensure execution of these programs cannot be co-opted.

Verify that System Executables Have Root Ownershipxccdf_org.ssgproject.content_rule_file_ownership_binary_dirs medium

Verify that System Executables Have Root Ownership

Rule IDxccdf_org.ssgproject.content_rule_file_ownership_binary_dirs
Result
pass
Time2016-07-11T14:19:29
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, http://iase.disa.mil/stigs/cci/Pages/index.aspx

Description

System executables are stored in the following directories by default:

/bin
/sbin
/usr/bin
/usr/libexec
/usr/local/bin
/usr/local/sbin
/usr/sbin
All files in these directories should be owned by the root user. If any file FILE in these directories is found to be owned by a user other than root, correct its ownership with the following command:
$ sudo chown root FILE

Rationale

System binaries are executed by privileged users as well as system services, and restrictive permissions are necessary to ensure that their execution of these programs cannot be co-opted.

Verify that All World-Writable Directories Have Sticky Bits Setxccdf_org.ssgproject.content_rule_dir_perms_world_writable_sticky_bits low

Verify that All World-Writable Directories Have Sticky Bits Set

Rule IDxccdf_org.ssgproject.content_rule_dir_perms_world_writable_sticky_bits
Result
pass
Time2016-07-11T14:19:34
Severitylow
Identifiers and References

identifiers: 

references:  AC-6, 1.1.17, Test attestation on 20120929 by swells

Description

When the so-called 'sticky bit' is set on a directory, only the owner of a given file may remove that file from the directory. Without the sticky bit, any user with write access to a directory may remove any file in the directory. Setting the sticky bit prevents users from removing each other's files. In cases where there is no reason for a directory to be world-writable, a better solution is to remove that permission rather than to set the sticky bit. However, if a directory is used by a particular application, consult that application's documentation instead of blindly changing modes.
To set the sticky bit on a world-writable directory DIR, run the following command:

$ sudo chmod +t DIR

Rationale

Failing to set the sticky bit on public directories allows unauthorized users to delete files in the directory structure.

The only authorized public directories are those temporary directories supplied with the system, or those designed to be temporary file repositories. The setting is normally reserved for directories used by the system, by users for temporary file storage (such as /tmp), and for directories requiring global read/write access.

Ensure No World-Writable Files Existxccdf_org.ssgproject.content_rule_file_permissions_unauthorized_world_writable medium

Ensure No World-Writable Files Exist

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_unauthorized_world_writable
Result
pass
Time2016-07-11T14:20:05
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6

Description

It is generally a good idea to remove global (other) write access to a file when it is discovered. However, check with documentation for specific applications before making changes. Also, monitor for recurring world-writable files, as these may be symptoms of a misconfigured application or user account.

Rationale

Data in world-writable files can be modified by any user on the system. In almost all circumstances, files can be configured using a combination of user and group permissions to support whatever legitimate access is needed without the risk caused by world-writable files.

Ensure All SGID Executables Are Authorizedxccdf_org.ssgproject.content_rule_file_permissions_unauthorized_sgid low

Ensure All SGID Executables Are Authorized

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_unauthorized_sgid
Result
pass
Time2016-07-11T14:20:32
Severitylow
Identifiers and References

identifiers: 

references:  AC-6(1)

Description

The SGID (set group id) bit should be set only on files that were installed via authorized means. A straightforward means of identifying unauthorized SGID files is determine if any were not installed as part of an RPM package, which is cryptographically verified. Investigate the origin of any unpackaged SGID files.

Rationale

Executable files with the SGID permission run with the privileges of the owner of the file. SGID files of uncertain provenance could allow for unprivileged users to elevate privileges. The presence of these files should be strictly controlled on the system.

Ensure All SUID Executables Are Authorizedxccdf_org.ssgproject.content_rule_file_permissions_unauthorized_suid low

Ensure All SUID Executables Are Authorized

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_unauthorized_suid
Result
fail
Time2016-07-11T14:20:58
Severitylow
Identifiers and References

identifiers: 

references:  AC-6(1)

Description

The SUID (set user id) bit should be set only on files that were installed via authorized means. A straightforward means of identifying unauthorized SGID files is determine if any were not installed as part of an RPM package, which is cryptographically verified. Investigate the origin of any unpackaged SUID files.

Rationale

Executable files with the SUID permission run with the privileges of the owner of the file. SUID files of uncertain provenance could allow for unprivileged users to elevate privileges. The presence of these files should be strictly controlled on the system.

Ensure All Files Are Owned by a Userxccdf_org.ssgproject.content_rule_no_files_unowned_by_user medium

Ensure All Files Are Owned by a User

Rule IDxccdf_org.ssgproject.content_rule_no_files_unowned_by_user
Result
pass
Time2016-07-11T14:21:28
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, CM-6(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-020360

Description

If any files are not owned by a user, then the cause of their lack of ownership should be investigated. Following this, the files should be deleted or assigned to an appropriate user.

Rationale

Unowned files do not directly imply a security problem, but they are generally a sign that something is amiss. They may be caused by an intruder, by incorrect software installation or draft software removal, or by failure to remove all files belonging to a deleted account. The files should be repaired so they will not cause problems when accounts are created in the future, and the cause should be discovered and addressed.

Ensure All Files Are Owned by a Groupxccdf_org.ssgproject.content_rule_file_permissions_ungroupowned medium

Ensure All Files Are Owned by a Group

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_ungroupowned
Result
pass
Time2016-07-11T14:21:59
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, IA-2, 366, SRG-OS-000480-GPOS-00227, RHEL-07-020370

Description

If any files are not owned by a group, then the cause of their lack of group-ownership should be investigated. Following this, the files should be deleted or assigned to an appropriate group.

Rationale

Unowned files do not directly imply a security problem, but they are generally a sign that something is amiss. They may be caused by an intruder, by incorrect software installation or draft software removal, or by failure to remove all files belonging to a deleted account. The files should be repaired so they will not cause problems when accounts are created in the future, and the cause should be discovered and addressed.

Ensure All World-Writable Directories Are Owned by a System Accountxccdf_org.ssgproject.content_rule_dir_perms_world_writable_system_owned low

Ensure All World-Writable Directories Are Owned by a System Account

Rule IDxccdf_org.ssgproject.content_rule_dir_perms_world_writable_system_owned
Result
pass
Time2016-07-11T14:22:04
Severitylow
Identifiers and References

identifiers: 

references:  AC-6, Test attestation on 20120929 by swells

Description

All directories in local partitions which are world-writable should be owned by root or another system account. If any world-writable directories are not owned by a system account, this should be investigated. Following this, the files should be deleted or assigned to an appropriate group.

Rationale

Allowing a user account to own a world-writable directory is undesirable because it allows the owner of that directory to remove or replace any files that may be placed in the directory by other users.

Set Daemon Umaskxccdf_org.ssgproject.content_rule_umask_for_daemons low

Set Daemon Umask

Rule IDxccdf_org.ssgproject.content_rule_umask_for_daemons
Result
pass
Time2016-07-11T14:22:04
Severitylow
Identifiers and References

identifiers: 

references:  AC-6, 3.1, Test attestation on 20140912 by JL

Description

The file /etc/init.d/functions includes initialization parameters for most or all daemons started at boot time. The default umask of 022 prevents creation of group- or world-writable files. To set the default umask for daemons, edit the following line, inserting 022 or 027 for UMASK appropriately:

umask 022
Setting the umask to too restrictive a setting can cause serious errors at runtime. Many daemons on the system already individually restrict themselves to a umask of 077 in their own init scripts.

Rationale

The umask influences the permissions assigned to files created by a process at run time. An unnecessarily permissive umask could result in files being created with insecure permissions.

Disable Core Dumps for All Usersxccdf_org.ssgproject.content_rule_disable_users_coredumps low

Disable Core Dumps for All Users

Rule IDxccdf_org.ssgproject.content_rule_disable_users_coredumps
Result
pass
Time2016-07-11T14:22:04
Severitylow
Identifiers and References

identifiers: 

references:  SC-5, 1.6.1

Description

To disable core dumps for all users, add the following line to /etc/security/limits.conf:

*     hard   core    0

Rationale

A core dump includes a memory image taken at the time the operating system terminates an application. The memory image could contain sensitive data and is generally useful only for developers trying to debug problems.

Disable Core Dumps for SUID programsxccdf_org.ssgproject.content_rule_sysctl_fs_suid_dumpable low

Disable Core Dumps for SUID programs

Rule IDxccdf_org.ssgproject.content_rule_sysctl_fs_suid_dumpable
Result
pass
Time2016-07-11T14:22:04
Severitylow
Identifiers and References

identifiers: 

references:  SI-11, 1.6.1

Description

To set the runtime status of the fs.suid_dumpable kernel parameter, run the following command:

$ sudo sysctl -w fs.suid_dumpable=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
fs.suid_dumpable = 0

Rationale

The core dump of a setuid program is more likely to contain sensitive data, as the program itself runs with greater privileges than the user who initiated execution of the program. Disabling the ability for any setuid program to write a core file decreases the risk of unauthorized access of such data.

Enable ExecShieldxccdf_org.ssgproject.content_rule_sysctl_kernel_exec_shield medium

Enable ExecShield

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_exec_shield
Result
pass
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  SC-39, 2530, Test attestation on 20121024 by DS

Description

By default on Red Hat Enterprise Linux 7 64-bit systems, ExecShield is enabled and can only be disabled if the hardware does not support ExecShield or is disabled in /etc/default/grub. For Red Hat Enterprise Linux 7 32-bit systems, sysctl can be used to enable ExecShield.

Rationale

ExecShield uses the segmentation feature on all x86 systems to prevent execution in memory higher than a certain address. It writes an address as a limit in the code segment descriptor, to control where code can be executed, on a per-process basis. When the kernel places a process's memory regions such as the stack and heap higher than this address, the hardware prevents execution in that address range. This is enabled by default on the latest Red Hat and Fedora systems if supported by the hardware.

Enable Randomized Layout of Virtual Address Spacexccdf_org.ssgproject.content_rule_sysctl_kernel_randomize_va_space medium

Enable Randomized Layout of Virtual Address Space

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_randomize_va_space
Result
error
Time2016-07-11T14:24:56
Severitymedium
Identifiers and References

identifiers: 

references:  SC-30(2), 1.6.1, Test attestation on 20121024 by DS

Description

To set the runtime status of the kernel.randomize_va_space kernel parameter, run the following command:

$ sudo sysctl -w kernel.randomize_va_space=2
If this is not the system's default value, add the following line to /etc/sysctl.conf:
kernel.randomize_va_space = 2

Rationale

Address space layout randomization (ASLR) makes it more difficult for an attacker to predict the location of attack code they have introduced into a process's address space during an attempt at exploitation. Additionally, ASLR makes it more difficult for an attacker to know the location of existing code in order to re-purpose it using return oriented programming (ROP) techniques.

Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:

function replace_or_append {
  local config_file=$1
  local key=$2
  local value=$3
  local cce=$4
  local format=$5

  # Check sanity of the input
  if [ $# -lt "3" ]
  then
        echo "Usage: replace_or_append 'config_file_location' 'key_to_search' 'new_value'"
        echo
        echo "If symlinks need to be taken into account, add yes/no to the last argument"
        echo "to allow to 'follow_symlinks'."
        echo "Aborting."
        exit 1
  fi

  # Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
  # Otherwise, regular sed command will do.
  if test -L $config_file; then
    sed_command="sed -i --follow-symlinks"
  else
    sed_command="sed -i"
  fi

  # Test that the cce arg is not empty or does not equal CCENUM.
  # If CCENUM exists, it means that there is no CCE assigned.
  if ! [ "x$cce" = x ] && [ "$cce" != 'CCENUM' ]; then
    cce="CCE-${cce}"
  else
    cce="CCE"
  fi

  # Strip any search characters in the key arg so that the key can be replaced without
  # adding any search characters to the config file.
  stripped_key=${key//[!a-zA-Z]/}

  # If there is no print format specified in the last arg, use the default format.
  if ! [ "x$format" = x ] ; then
    printf -v formatted_output "$format" $stripped_key $value
  else
    formatted_output="$stripped_key = $value"
  fi

  # If the key exists, change it. Otherwise, add it to the config_file.
  if `grep -qi $key $config_file` ; then
    $sed_command "s/$key.*/$formatted_output/g" $config_file
  else
    echo -ne "\n# Per $cce: Set $formatted_output in $config_file" >> $config_file
    echo -ne "\n$formatted_output" >> $config_file
  fi

}

replace_or_append '/etc/sysctl.conf' '^kernel.randomize_va_space' '2' 'CCENUM'
Install PAE Kernel on Supported 32-bit x86 Systemsxccdf_org.ssgproject.content_rule_install_PAE_kernel_on_x86-32 low

Install PAE Kernel on Supported 32-bit x86 Systems

Rule IDxccdf_org.ssgproject.content_rule_install_PAE_kernel_on_x86-32
Result
pass
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  CM-6(b)

Description

Systems that are using the 64-bit x86 kernel package do not need to install the kernel-PAE package because the 64-bit x86 kernel already includes this support. However, if the system is 32-bit and also supports the PAE and NX features as determined in the previous section, the kernel-PAE package should be installed to enable XD or NX support:

$ sudo yum install kernel-PAE
The installation process should also have configured the bootloader to load the new kernel at boot. Verify this at reboot and modify /etc/default/grub if necessary.

Rationale

On 32-bit systems that support the XD or NX bit, the vendor-supplied PAE kernel is required to enable either Execute Disable (XD) or No Execute (NX) support.

Warnings
warning  The kernel-PAE package should not be installed on older systems that do not support the XD or NX bit, as this may prevent them from booting.
Enable NX or XD Support in the BIOSxccdf_org.ssgproject.content_rule_bios_enable_execution_restrictions low

Enable NX or XD Support in the BIOS

Rule IDxccdf_org.ssgproject.content_rule_bios_enable_execution_restrictions
Result
notchecked
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  CM-6(b)

Description

Reboot the system and enter the BIOS or Setup configuration menu. Navigate the BIOS configuration menu and make sure that the option is enabled. The setting may be located under a Security section. Look for Execute Disable (XD) on Intel-based systems and No Execute (NX) on AMD-based systems.

Rationale

Computers with the ability to prevent this type of code execution frequently put an option in the BIOS that will allow users to turn the feature on or off at will.

Evaluation messages
info 
No candidate or applicable check found.
Restrict Access to Kernel Message Bufferxccdf_org.ssgproject.content_rule_sysctl_kernel_dmesg_restrict low

Restrict Access to Kernel Message Buffer

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_dmesg_restrict
Result
pass
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  SI-11, 1314

Description

To set the runtime status of the kernel.dmesg_restrict kernel parameter, run the following command:

$ sudo sysctl -w kernel.dmesg_restrict=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
kernel.dmesg_restrict = 1

Rationale

Unprivileged access to the kernel syslog can expose sensitive kernel address information.

Ensure SELinux Not Disabled in /etc/default/grubxccdf_org.ssgproject.content_rule_enable_selinux_bootloader medium

Ensure SELinux Not Disabled in /etc/default/grub

Rule IDxccdf_org.ssgproject.content_rule_enable_selinux_bootloader
Result
pass
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  AC-3, AC-3(3), AC-6, AU-9, 22, 32, 1.4.1, Test attestation on 20121024 by DS

Description

SELinux can be disabled at boot time by an argument in /etc/default/grub. Remove any instances of selinux=0 from the kernel arguments in that file to prevent SELinux from being disabled at boot.

Rationale

Disabling a major host protection feature, such as SELinux, at boot time prevents it from confining system services at boot time. Further, it increases the chances that it will remain off during system operation.

Ensure SELinux State is Enforcingxccdf_org.ssgproject.content_rule_selinux_state medium

Ensure SELinux State is Enforcing

Rule IDxccdf_org.ssgproject.content_rule_selinux_state
Result
pass
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  AC-3, AC-3(3), AC-4, AC-6, AU-9, http://iase.disa.mil/stigs/cci/Pages/index.aspx, 1.4.2, Test attestation on 20121024 by DS

Description

The SELinux state should be set to enforcing at system boot time. In the file /etc/selinux/config, add or correct the following line to configure the system to boot into enforcing mode:

SELINUX=enforcing

Rationale

Setting the SELinux state to enforcing ensures SELinux is able to confine potentially compromised processes to the security policy, which is designed to prevent them from causing damage to the system or further elevating their privileges.

Configure SELinux Policyxccdf_org.ssgproject.content_rule_selinux_policytype low

Configure SELinux Policy

Rule IDxccdf_org.ssgproject.content_rule_selinux_policytype
Result
pass
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  AC-3, AC-3(3), AC-4, AC-6, AU-9, http://iase.disa.mil/stigs/cci/Pages/index.aspx, 1.4.3, Test attestation on 20121024 by DS

Description

The SELinux targeted policy is appropriate for general-purpose desktops and servers, as well as systems in many other roles. To configure the system to use this policy, add or correct the following line in /etc/selinux/config:

SELINUXTYPE=targeted
Other policies, such as mls, provide additional security labeling and greater confinement but are not compatible with many general-purpose use cases.

Rationale

Setting the SELinux policy to targeted or a more specialized policy ensures the system will confine processes that are likely to be targeted for exploitation, such as network or system services. Note: During the development or debugging of SELinux modules, it is common to temporarily place non-production systems in permissive mode. In such temporary cases, SELinux policies should be developed, and once work is completed, the system should be reconfigured to targeted.

Uninstall setroubleshoot Packagexccdf_org.ssgproject.content_rule_package_setroubleshoot_removed low

Uninstall setroubleshoot Package

Rule IDxccdf_org.ssgproject.content_rule_package_setroubleshoot_removed
Result
pass
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  1.4.4

Description

The SETroubleshoot service notifies desktop users of SELinux denials. The service provides information around configuration errors, unauthorized intrusions, and other potential errors. The setroubleshoot package can be removed with the following command:

$ sudo yum erase setroubleshoot

Rationale

The SETroubleshoot service is an unnecessary daemon to have running on a server

Uninstall mcstrans Packagexccdf_org.ssgproject.content_rule_package_mcstrans_removed low

Uninstall mcstrans Package

Rule IDxccdf_org.ssgproject.content_rule_package_mcstrans_removed
Result
pass
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

Description

The mcstransd daemon provides category label information to client processes requesting information. The label translations are defined in /etc/selinux/targeted/setrans.conf. The mcstrans package can be removed with the following command:

$ sudo yum erase mcstrans

Rationale

Since this service is not used very often, disable it to reduce the amount of potentially vulnerable code running on the system. NOTE: This rule was added in support of the CIS RHEL6 v1.2.0 benchmark. Please note that Red Hat does not feel this rule is security relevant.

Ensure No Daemons are Unconfined by SELinuxxccdf_org.ssgproject.content_rule_selinux_confinement_of_daemons medium

Ensure No Daemons are Unconfined by SELinux

Rule IDxccdf_org.ssgproject.content_rule_selinux_confinement_of_daemons
Result
notselected
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, AU-9, CM-7, 1.4.6

Description

Daemons for which the SELinux policy does not contain rules will inherit the context of the parent process. Because daemons are launched during startup and descend from the init process, they inherit the initrc_t context.

To check for unconfined daemons, run the following command:

$ sudo ps -eZ | egrep "initrc" | egrep -vw "tr|ps|egrep|bash|awk" | tr ':' ' ' | awk '{ print $NF }'
It should produce no output in a well-configured system.

Rationale

Daemons which run with the initrc_t context may cause AVC denials, or allow privileges that the daemon does not require.

Ensure No Device Files are Unlabeled by SELinuxxccdf_org.ssgproject.content_rule_selinux_all_devicefiles_labeled low

Ensure No Device Files are Unlabeled by SELinux

Rule IDxccdf_org.ssgproject.content_rule_selinux_all_devicefiles_labeled
Result
fail
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  AC-6, AU-9, CM-7, 22, 32, Test attestation on 20121024 by DS

Description

Device files, which are used for communication with important system resources, should be labeled with proper SELinux types. If any device files carry the SELinux type device_t, report the bug so that policy can be corrected. Supply information about what the device is and what programs use it.

Rationale

If a device file carries the SELinux type device_t, then SELinux cannot properly restrict access to the device file.

Direct root Logins Not Allowedxccdf_org.ssgproject.content_rule_no_direct_root_logins medium

Direct root Logins Not Allowed

Rule IDxccdf_org.ssgproject.content_rule_no_direct_root_logins
Result
pass
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  IA-2(1), 6.4, Test attestation on 20121024 by DS

Description

To further limit access to the root account, administrators can disable root logins at the console by editing the /etc/securetty file. This file lists all devices the root user is allowed to login to. If the file does not exist at all, the root user can login through any communication device on the system, whether via the console or via a raw network interface. This is dangerous as user can login to his machine as root via Telnet, which sends the password in plain text over the network. By default, Red Hat Enteprise Linux's /etc/securetty file only allows the root user to login at the console physically attached to the machine. To prevent root from logging in, remove the contents of this file. To prevent direct root logins, remove the contents of this file by typing the following command:

$ sudo echo > /etc/securetty

Rationale

Disabling direct root logins ensures proper accountability and multifactor authentication to privileged accounts. Users will first login, then escalate to privileged (root) access via su / sudo. This is required for FISMA Low and FISMA Moderate systems.

Restrict Serial Port Root Loginsxccdf_org.ssgproject.content_rule_restrict_serial_port_logins low

Restrict Serial Port Root Logins

Rule IDxccdf_org.ssgproject.content_rule_restrict_serial_port_logins
Result
pass
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  AC-6(2), 770, Test attestation on 20121024 by DS

Description

To restrict root logins on serial ports, ensure lines of this form do not appear in /etc/securetty:

ttyS0
ttyS1

Rationale

Preventing direct root login to serial port interfaces helps ensure accountability for actions taken on the systems using the root account.

Restrict Web Browser Use for Administrative Accountsxccdf_org.ssgproject.content_rule_no_root_webbrowsing low

Restrict Web Browser Use for Administrative Accounts

Rule IDxccdf_org.ssgproject.content_rule_no_root_webbrowsing
Result
notchecked
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

Description

Enforce policy requiring administrative accounts use web browsers only for local service administration.

Rationale

If a browser vulnerability is exploited while running with administrative privileges, the entire system could be compromised. Specific exceptions for local service administration should be documented in site-defined policy.

Evaluation messages
info 
No candidate or applicable check found.
Ensure that System Accounts Do Not Run a Shell Upon Loginxccdf_org.ssgproject.content_rule_no_shelllogin_for_systemaccounts medium

Ensure that System Accounts Do Not Run a Shell Upon Login

Rule IDxccdf_org.ssgproject.content_rule_no_shelllogin_for_systemaccounts
Result
pass
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  AC-2, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20121024 by DS

Description

Some accounts are not associated with a human user of the system, and exist to perform some administrative function. Should an attacker be able to log into these accounts, they should not be granted access to a shell.

The login shell for each local account is stored in the last field of each line in /etc/passwd. System accounts are those user accounts with a user ID less than UID_MIN, where value of UID_MIN directive is set in /etc/login.defs configuration file. In the default configuration UID_MIN is set to 1000, thus system accounts are those user accounts with a user ID less than 1000. The user ID is stored in the third field. If any system account SYSACCT (other than root) has a login shell, disable it with the command:

$ sudo usermod -s /sbin/nologin SYSACCT

Rationale

Ensuring shells are not given to system accounts upon login makes it more difficult for attackers to make use of system accounts.

Warnings
warning  Do not perform the steps in this section on the root account. Doing so might cause the system to become inaccessible.
Verify Only Root Has UID 0xccdf_org.ssgproject.content_rule_accounts_no_uid_except_zero high

Verify Only Root Has UID 0

Rule IDxccdf_org.ssgproject.content_rule_accounts_no_uid_except_zero
Result
pass
Time2016-07-11T14:22:05
Severityhigh
Identifiers and References

identifiers: 

references:  AC-6, IA-2(1), IA-4, 366, SRG-OS-000480-GPOS-00227, RHEL-07-020310, Test attestation on 20121024 by DS

Description

If any account other than root has a UID of 0, this misconfiguration should be investigated and the accounts other than root should be removed or have their UID changed.
If the account is associated with system commands or applications the UID should be changed to one greater than "0" but less than "1000." Otherwise assign a UID greater than "1000" that has not already been assigned.

Rationale

An account has root authority if it has a UID of 0. Multiple accounts with a UID of 0 afford more opportunity for potential intruders to guess a password for a privileged account. Proper configuration of sudo is recommended to afford multiple system administrators access to root privileges in an accountable manner.

Root Path Must Be Vendor Defaultxccdf_org.ssgproject.content_rule_root_path_default low

Root Path Must Be Vendor Default

Rule IDxccdf_org.ssgproject.content_rule_root_path_default
Result
notchecked
Time2016-07-11T14:22:05
Severitylow
Identifiers and References

identifiers: 

references:  SA-8, Test attestation on 20121024 by DS

Description

Assuming root shell is bash, edit the following files:

~/.profile
~/.bashrc
Change any PATH variables to the vendor default for root and remove any empty PATH entries or references to relative paths.

Rationale

The root account's executable search path must be the vendor default, and must contain only absolute paths.

Evaluation messages
info 
No candidate or applicable check found.
Prevent Log In to Accounts With Empty Passwordxccdf_org.ssgproject.content_rule_no_empty_passwords high

Prevent Log In to Accounts With Empty Password

Rule IDxccdf_org.ssgproject.content_rule_no_empty_passwords
Result
pass
Time2016-07-11T14:22:05
Severityhigh
Identifiers and References

identifiers: 

references:  AC-6, IA-5(b), IA-5(c), IA-5(1)(a), 366, SRG-OS-000480-GPOS-00227, RHEL-07-010260, Req-8.2.3, Test attestation on 20121024 by DS

Description

If an account is configured for password authentication but does not have an assigned password, it may be possible to log into the account without authentication. Remove any instances of the nullok option in /etc/pam.d/system-auth to prevent logins with empty passwords.

Rationale

If an account has an empty password, anyone could log in and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments.

Verify All Account Password Hashes are Shadowedxccdf_org.ssgproject.content_rule_accounts_password_all_shadowed medium

Verify All Account Password Hashes are Shadowed

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_all_shadowed
Result
pass
Time2016-07-11T14:22:05
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(h), http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-8.2.1, Test attestation on 20121024 by DS

Description

If any password hashes are stored in /etc/passwd (in the second field, instead of an x), the cause of this misconfiguration should be investigated. The account should have its password reset and the hash should be properly stored, or the account should be deleted entirely.

Rationale

The hashes for all user account passwords should be stored in the file /etc/shadow and never in /etc/passwd, which is readable by all users.

All GIDs referenced in /etc/passwd must be defined in /etc/groupxccdf_org.ssgproject.content_rule_gid_passwd_group_same low

All GIDs referenced in /etc/passwd must be defined in /etc/group

Rule IDxccdf_org.ssgproject.content_rule_gid_passwd_group_same
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  IA-2, 764, SRG-OS-000104-GPOS-00051, RHEL-07-020300, Req-8.5.a, Test attestation on 20121024 by DS

Description

Add a group to the system for each GID referenced without a corresponding group.

Rationale

If a user is assigned the Group Identifier (GID) of a group not existing on the system, and a group with the Gruop Identifier (GID) is subsequently created, the user may have unintended rights to any files associated with the group.

Verify No netrc Files Existxccdf_org.ssgproject.content_rule_no_netrc_files medium

Verify No netrc Files Exist

Rule IDxccdf_org.ssgproject.content_rule_no_netrc_files
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(h), AC-3, 196

Description

The .netrc files contain login information used to auto-login into FTP servers and reside in the user's home directory. These files may contain unencrypted passwords to remote FTP servers making them susceptible to access by unauthorized users and should not be used. Any .netrc files should be removed.

Rationale

Unencrypted passwords for remote FTP servers may be stored in .netrc files. DoD policy requires passwords be encrypted in storage and not used in access scripts.

Set Password Retry Prompts Permitted Per-Sessionxccdf_org.ssgproject.content_rule_accounts_password_pam_retry low

Set Password Retry Prompts Permitted Per-Session

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_retry
Result
notselected
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  CM-6(b), IA-5(c), 366, 6.3.2, SRG-OS-000480-GPOS-00225, RHEL-07-010410, Test attestation on 20140925 by swells

Description

To configure the number of retry prompts that are permitted per-session:

Edit the pam_pwquality.so statement in /etc/pam.d/system-auth to show retry=3, or a lower value if site policy is more restrictive.

The DoD requirement is a maximum of 3 prompts per session.

Rationale

Setting the password retry prompts that are permitted on a per-session basis to a low value requires some software, such as SSH, to re-connect. This can slow down and draw additional attention to some types of password-guessing attacks. Note that this is different from account lockout, which is provided by the pam_faillock module.

Set Password to Maximum of Three Consecutive Repeating Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_maxrepeat medium

Set Password to Maximum of Three Consecutive Repeating Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_maxrepeat
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5, IA-5(c), 195, SRG-OS-000072-GPOS-00040, RHEL-07-010150

Description

The pam_pwquality module's maxrepeat parameter controls requirements for consecutive repeating characters. When set to a positive number, it will reject passwords which contain more than that number of consecutive characters. Modify the maxrepeat setting in /etc/security/pwquality.conf to equal 2 to prevent a run of (2 + 1) or more identical characters.

Rationale

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised. Passwords with excessive repeating characters may be more vulnerable to password-guessing attacks.

Set Password to Maximum of Consecutive Repeating Characters from Same Character Classxccdf_org.ssgproject.content_rule_accounts_password_pam_maxclassrepeat low

Set Password to Maximum of Consecutive Repeating Characters from Same Character Class

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_maxclassrepeat
Result
error
Time2016-07-11T14:24:56
Severitylow
Identifiers and References

identifiers: 

references:  IA-5, IA-5(c), 195, SRG-OS-000072-GPOS-00040, RHEL-07-010160

Description

The pam_pwquality module's maxclassrepeat parameter controls requirements for consecutive repeating characters from the same character class. When set to a positive number, it will reject passwords which contain more than that number of consecutive characters from the same character class. Modify the maxclassrepeat setting in /etc/security/pwquality.conf to equal 2 to prevent a run of (2 + 1) or more identical characters.

Rationale

Use of a complex password helps to increase the time and resources required to comrpomise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.
Password complexity is one factor of several that determines how long it takes to crack a password. The more complex a password, the greater the number of possible combinations that need to be tested before the password is compromised.

Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:

var_password_pam_maxclassrepeat="2"

if grep -q "maxclassrepeat=" /etc/security/pwquality.conf ; then   
	echo "maxclassrepeat = $var_password_pam_maxclassrepeat" >> /etc/security/pwquality.conf
fi
Set Password Strength Minimum Digit Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_dcredit medium

Set Password Strength Minimum Digit Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_dcredit
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(1)(a), IA-5(b), IA-5(c), 194, 194, SRG-OS-000071-GPOS-00039, Req-8.2.3, 6.3.2, RHEL-07-010110, Test attestation on 20121024 by DS

Description

The pam_pwquality module's dcredit parameter controls requirements for usage of digits in a password. When set to a negative number, any password will be required to contain that many digits. When set to a positive number, pam_pwquality will grant +1 additional length credit for each digit. Modify the dcredit setting in /etc/security/pwquality.conf to require the use of a digit in passwords.

Rationale

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring digits makes password guessing attacks more difficult by ensuring a larger search space.

Set Password Minimum Lengthxccdf_org.ssgproject.content_rule_accounts_password_pam_minlen medium

Set Password Minimum Length

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_minlen
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(1)(a), 205, SRG-OS-000078-GPOS-00046, Req-8.2.3, 6.3.2, RHEL-07-010250, Test attestation on 20140928 by swells

Description

The pam_pwquality module's minlen parameter controls requirements for minimum characters required in a password. Add minlen=15 after pam_pwquality to set minimum password length requirements.

Rationale

The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.
Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Use of more characters in a password helps to exponentially increase the time and/or resources required to compromose the password.

Set Password Strength Minimum Uppercase Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_ucredit low

Set Password Strength Minimum Uppercase Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_ucredit
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(a), 192, SRG-OS-000069-GPOS-00037, RHEL-07-010090, Req-8.2.3, 6.3.2, Test attestation on 20121024 by DS

Description

The pam_pwquality module's ucredit= parameter controls requirements for usage of uppercase letters in a password. When set to a negative number, any password will be required to contain that many uppercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each uppercase character. Modify the ucredit setting in /etc/security/pwquality.conf to require the use of an uppercase character in passwords.

Rationale

Use of a complex password helps to increase the time and resources reuiqred to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.
Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.

Set Password Strength Minimum Special Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_ocredit medium

Set Password Strength Minimum Special Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_ocredit
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(a), 1619, SRG-OS-000266-GPOS-00101, RHEL-07-010120, Test attestation on 20121024 by DS

Description

The pam_pwquality module's ocredit= parameter controls requirements for usage of special (or "other") characters in a password. When set to a negative number, any password will be required to contain that many special characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each special character. Modify the ocredit setting in /etc/security/pwquality.conf to equal -1 to require use of a special character in passwords.

Rationale

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring a minimum number of special characters makes password guessing attacks more difficult by ensuring a larger search space.

Set Password Strength Minimum Lowercase Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_lcredit medium

Set Password Strength Minimum Lowercase Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_lcredit
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(a), 193, SRG-OS-000070-GPOS-00038, Req-8.2.3, RHEL-07-010100, Test attestation on 20121024 by DS

Description

The pam_pwquality module's lcredit parameter controls requirements for usage of lowercase letters in a password. When set to a negative number, any password will be required to contain that many lowercase characters. When set to a positive number, pam_pwquality will grant +1 additional length credit for each lowercase character. Modify the lcredit setting in /etc/security/pwquality.conf to require the use of a lowercase character in passwords.

Rationale

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possble combinations that need to be tested before the password is compromised. Requiring a minimum number of lowercase characters makes password guessing attacks more difficult by ensuring a larger search space.

Set Password Strength Minimum Different Charactersxccdf_org.ssgproject.content_rule_accounts_password_pam_difok medium

Set Password Strength Minimum Different Characters

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_difok
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(b), 195, SRG-OS-000072-GPOS-00040, RHEL-07-010130, Test attestation on 20121024 by DS

Description

The pam_pwquality module's difok parameter sets the number of characters in a password that must not be present in and old password during a password change. Modify the difok setting in /etc/security/pwquality.conf to equal 5 to require differing characters when changing passwords.

Rationale

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute–force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised. Requiring a minimum number of different characters during password changes ensures that newly changed passwords should not resemble previously compromised ones. Note that passwords which are changed on compromised systems will still be compromised, however.

Set Password Strength Minimum Different Categoriesxccdf_org.ssgproject.content_rule_accounts_password_pam_minclass medium

Set Password Strength Minimum Different Categories

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_minclass
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5, 195, SRG-OS-000072-GPOS-00040, RHEL-07-010140, Test attestation on 20140626 by JL

Description

The pam_pwquality module's minclass parameter controls requirements for usage of different character classes, or types, of character that must exist in a password before it is considered valid. For example, setting this value to three (3) requires that any password must have characters from at least three different categories in order to be approved. The default value is zero (0), meaning there are no required classes. There are four categories available:

* Upper-case characters
* Lower-case characters
* Digits
* Special characters (for example, punctuation)
Modify the minclass setting in /etc/security/pwquality.conf entry to require 4 differing categories of characters when changing passwords.

Rationale

Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised. Requiring a minimum number of character categories makes password guessing attacks more difficult by ensuring a larger search space.

Set Deny For Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny medium

Set Deny For Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-7(b), 2238, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005, RHEL-07-010370, Req-8.1.6, 6.3.3

Description

To configure the system to lock out accounts after a number of incorrect login attempts using pam_faillock.so, modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • add the following line immediately before the pam_unix.so statement in the AUTH section:
    auth required pam_faillock.so preauth silent deny=3 unlock_time=604800 fail_interval=900
  • add the following line immediately after the pam_unix.so statement in the AUTH section:
    auth [default=die] pam_faillock.so authfail deny=3 unlock_time=604800 fail_interval=900
  • add the following line immediately before the pam_unix.so statement in the ACCOUNT section:
    account required pam_faillock.so

Rationale

Locking out user accounts after a number of incorrect attempts prevents direct password guessing attacks.

Set Lockout Time For Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_unlock_time medium

Set Lockout Time For Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_unlock_time
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-7(b), 002238, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005, RHEL-07-010371, Req-8.1.7, 6.3.3

Description

To configure the system to lock out accounts after a number of incorrect login attempts and require an administrator to unlock the account using pam_faillock.so, modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • add the following line immediately before the pam_unix.so statement in the AUTH section:
    auth required pam_faillock.so preauth silent deny=3 unlock_time=604800 fail_interval=900
  • add the following line immediately after the pam_unix.so statement in the AUTH section:
    auth [default=die] pam_faillock.so authfail deny=3 unlock_time=604800 fail_interval=900
  • add the following line immediately before the pam_unix.so statement in the ACCOUNT section:
    account required pam_faillock.so

Rationale

Locking out user accounts after a number of incorrect attempts prevents direct password guessing attacks. Ensuring that an administrator is involved in unlocking locked accounts draws appropriate attention to such situations.

Configure the root Account for Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny_root medium

Configure the root Account for Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny_root
Result
notselected
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-7(b), 2238, SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005, RHEL-07-010372

Description

To configure the system to lock out the root account after a number of incorrect login attempts using pam_faillock.so, modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • modify the following line in the AUTH section to add even_deny_root:
    auth required pam_faillock.so preauth silent even_deny_root deny=3 unlock_time=604800 fail_interval=900
  • modify the following line in the AUTH section to add even_deny_root:
    auth [default=die] pam_faillock.so authfail even_deny_root deny=3 unlock_time=604800 fail_interval=900

Rationale

By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account.

Set Interval For Counting Failed Password Attemptsxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_interval medium

Set Interval For Counting Failed Password Attempts

Rule IDxccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_interval
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-7(a), 44, 21

Description

Utilizing pam_faillock.so, the fail_interval directive configures the system to lock out accounts after a number of incorrect login attempts. Modify the content of both /etc/pam.d/system-auth and /etc/pam.d/password-auth as follows:

  • add the following line immediately before the pam_unix.so statement in the AUTH section:
    auth required pam_faillock.so preauth silent deny=3 unlock_time=604800 fail_interval=900
  • add the following line immediately after the pam_unix.so statement in the AUTH section:
    auth [default=die] pam_faillock.so authfail deny=3 unlock_time=604800 fail_interval=900
  • add the following line immediately before the pam_unix.so statement in the ACCOUNT section:
    account required pam_faillock.so

Rationale

Locking out user accounts after a number of incorrect attempts within a specific period of time prevents direct password guessing attacks.

Limit Password Reusexccdf_org.ssgproject.content_rule_accounts_password_pam_unix_remember medium

Limit Password Reuse

Rule IDxccdf_org.ssgproject.content_rule_accounts_password_pam_unix_remember
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(f), IA-5(1)(e), 200, SRG-OS-000077-GPOS-00045, RHEL-07-010240, Req-8.2.5, 6.3.4, Test attestation on 20121024 by DS

Description

Do not allow users to reuse recent passwords. This can be accomplished by using the remember option for the pam_unix or pam_pwhistory PAM modules. In the file /etc/pam.d/system-auth, append remember=5 to the line which refers to the pam_unix.so or pam_pwhistory.somodule, as shown below:

  • for the pam_unix.so case:
    password sufficient pam_unix.so existing_options remember=5
  • for the pam_pwhistory.so case:
    password requisite pam_pwhistory.so existing_options remember=5
The DoD STIG requirement is 5 passwords.

Rationale

Preventing re-use of previous passwords helps ensure that a compromised password is not re-used by a user.

Set PAM's Password Hashing Algorithmxccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_systemauth medium

Set PAM's Password Hashing Algorithm

Rule IDxccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_systemauth
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(c), IA-7, 196, SRG-OS-000073-GPOS-00041, RHEL-07-010170, Req-8.2.1, 6.3.1, Test attestation on 20121024 by DS

Description

The PAM system service can be configured to only store encrypted representations of passwords. In /etc/pam.d/system-auth, the password section of the file controls which PAM modules execute during a password change. Set the pam_unix.so module in the password section to include the argument sha512, as shown below:

password    sufficient    pam_unix.so sha512 other arguments...

This will help ensure when local users change their passwords, hashes for the new passwords will be generated using the SHA-512 algorithm. This is the default.

Rationale

Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kepy in plain text. This setting ensures user and group account administration utilities are configured to store only encrypted representations of passwords. Additionally, the crypt_style configuration option ensures the use of a strong hashing algorithm that makes password cracking attacks more difficult.

Set Password Hashing Algorithm in /etc/login.defsxccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_logindefs medium

Set Password Hashing Algorithm in /etc/login.defs

Rule IDxccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_logindefs
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(c), IA-7, 196, SRG-OS-000073-GPOS-00041, RHEL-07-010180, Req-8.2.1, 6.3.1, Test attestation on 20121024 by DS

Description

In /etc/login.defs, add or correct the following line to ensure the system will use SHA-512 as the hashing algorithm:

ENCRYPT_METHOD SHA512

Rationale

Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kept in plain text. Using a stronger hashing algorithm makes password cracking attacks more difficult.

Set Password Hashing Algorithm in /etc/libuser.confxccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_libuserconf medium

Set Password Hashing Algorithm in /etc/libuser.conf

Rule IDxccdf_org.ssgproject.content_rule_set_password_hashing_algorithm_libuserconf
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(b), IA-5(c), IA-5(1)(c), IA-7, 196, SRG-OS-000073-GPOS-00041, RHEL-07-010190, Req-8.2.1, Test attestation on 20121026 by DS

Description

In /etc/libuser.conf, add or correct the following line in its [defaults] section to ensure the system will use the SHA-512 algorithm for password hashing:

crypt_style = sha512

Rationale

Passwords need to be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised. Passwords that are encrypted with a weak algorithm are no more protected than if they are kepy in plain text. This setting ensures user and group account administration utilities are configured to store only encrypted representations of passwords. Additionally, the crypt_style configuration option ensures the use of a strong hashing algorithm that makes password cracking attacks more difficult.

Ensure that Root's Path Does Not Include Relative Paths or Null Directoriesxccdf_org.ssgproject.content_rule_root_path_no_dot low

Ensure that Root's Path Does Not Include Relative Paths or Null Directories

Rule IDxccdf_org.ssgproject.content_rule_root_path_no_dot
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  CM-6(b), 366

Description

Ensure that none of the directories in root's path is equal to a single . character, or that it contains any instances that lead to relative path traversal, such as .. or beginning a path without the slash (/) character. Also ensure that there are no "empty" elements in the path, such as in these examples:

PATH=:/bin
PATH=/bin:
PATH=/bin::/sbin
These empty elements have the same effect as a single . character.

Rationale

Including these entries increases the risk that root could execute code from an untrusted location.

Ensure that Root's Path Does Not Include World or Group-Writable Directoriesxccdf_org.ssgproject.content_rule_accounts_root_path_dirs_no_write low

Ensure that Root's Path Does Not Include World or Group-Writable Directories

Rule IDxccdf_org.ssgproject.content_rule_accounts_root_path_dirs_no_write
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  CM-6(b), 366

Description

For each element in root's path, run:

# ls -ld DIR
and ensure that write permissions are disabled for group and other.

Rationale

Such entries increase the risk that root could execute code provided by unprivileged users, and potentially malicious code.

Ensure the Default Bash Umask is Set Correctlyxccdf_org.ssgproject.content_rule_accounts_umask_etc_bashrc low

Ensure the Default Bash Umask is Set Correctly

Rule IDxccdf_org.ssgproject.content_rule_accounts_umask_etc_bashrc
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  SA-8, 366, Test attestation on 20140912 by JL

Description

To ensure the default umask for users of the Bash shell is set properly, add or correct the umask setting in /etc/bashrc to read as follows:

umask 027

Rationale

The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.

Ensure the Default C Shell Umask is Set Correctlyxccdf_org.ssgproject.content_rule_accounts_umask_etc_csh_cshrc low

Ensure the Default C Shell Umask is Set Correctly

Rule IDxccdf_org.ssgproject.content_rule_accounts_umask_etc_csh_cshrc
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  SA-8, 366, Test attestation on 20140912 by JL

Description

To ensure the default umask for users of the C shell is set properly, add or correct the umask setting in /etc/csh.cshrc to read as follows:

umask 027

Rationale

The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.

Ensure the Default Umask is Set Correctly in /etc/profilexccdf_org.ssgproject.content_rule_accounts_umask_etc_profile low

Ensure the Default Umask is Set Correctly in /etc/profile

Rule IDxccdf_org.ssgproject.content_rule_accounts_umask_etc_profile
Result
pass
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  SA-8, 366, Test attestation on 20120929 by swells

Description

To ensure the default umask controlled by /etc/profile is set properly, add or correct the umask setting in /etc/profile to read as follows:

umask 027

Rationale

The umask value influences the permissions assigned to files when they are created. A misconfigured umask value could result in files with excessive permissions that can be read or written to by unauthorized users.

Set Interactive Session Timeoutxccdf_org.ssgproject.content_rule_accounts_tmout medium

Set Interactive Session Timeout

Rule IDxccdf_org.ssgproject.content_rule_accounts_tmout
Result
notselected
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-12, SC-10, 1133, 0361, SRG-OS-000163-GPOS-00072, RHEL-07-040160

Description

Terminating an idle session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been left unattended.

Rationale

Ensure the Logon Failure Delay is Set Correctly in login.defsxccdf_org.ssgproject.content_rule_accounts_logon_fail_delay low

Ensure the Logon Failure Delay is Set Correctly in login.defs

Rule IDxccdf_org.ssgproject.content_rule_accounts_logon_fail_delay
Result
fail
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  CM-6(b), 366, SRG-OS-000480-GPOS-00226, RHEL-07-010420

Description

To ensure the logon failure delay controlled by /etc/login.defs is set properly, add or correct the FAIL_DELAY setting in /etc/login.defs to read as follows:

FAIL_DELAY 4

Rationale

Increasing the time between a failed authentication attempt and re-prompting to enter credentials helps to slow a single-threaded brute force attack.

Ensure that User Home Directories are not Group-Writable or World-Readablexccdf_org.ssgproject.content_rule_file_permissions_home_dirs low

Ensure that User Home Directories are not Group-Writable or World-Readable

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_home_dirs
Result
fail
Time2016-07-11T14:22:06
Severitylow
Identifiers and References

identifiers: 

references:  AC-6(7), 225

Description

For each human user of the system, view the permissions of the user's home directory:

# ls -ld /home/USER
Ensure that the directory is not group-writable and that it is not world-readable. If necessary, repair the permissions:
# chmod g-w /home/USER
# chmod o-rwx /home/USER

Rationale

User home directories contain many configuration files which affect the behavior of a user's account. No user should ever have write permission to another user's home directory. Group shared directories can be configured in sub-directories or elsewhere in the filesystem if they are needed. Typically, user home directories should not be world-readable, as it would disclose file names to other users. If a subset of users need read access to one another's home directories, this can be provided using groups or ACLs.

Warnings
warning  This action may involve modifying user home directories. Notify your user community, and solicit input if appropriate, before making this type of change.
Verify /boot/grub2/grub.cfg User Ownershipxccdf_org.ssgproject.content_rule_file_user_owner_grub2_cfg medium

Verify /boot/grub2/grub.cfg User Ownership

Rule IDxccdf_org.ssgproject.content_rule_file_user_owner_grub2_cfg
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6(7), 225, Req-7.1, 1.5.1, Test attestation on 20121026 by DS

Description

The file /boot/grub2/grub.cfg should be owned by the root user to prevent destruction or modification of the file. To properly set the owner of /boot/grub2/grub.cfg, run the command:

$ sudo chown root /boot/grub2/grub.cfg

Rationale

Only root should be able to modify important boot parameters.

Verify /boot/grub2/grub.cfg Group Ownershipxccdf_org.ssgproject.content_rule_file_group_owner_grub2_cfg medium

Verify /boot/grub2/grub.cfg Group Ownership

Rule IDxccdf_org.ssgproject.content_rule_file_group_owner_grub2_cfg
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6(7), 225, Req-7.1, 1.5.1, Test attestation on 20121026 by DS

Description

The file /boot/grub2/grub.cfg should be group-owned by the root group to prevent destruction or modification of the file. To properly set the group owner of /boot/grub2/grub.cfg, run the command:

$ sudo chgrp root /boot/grub2/grub.cfg

Rationale

The root group is a highly-privileged group. Furthermore, the group-owner of this file should not have any access privileges anyway.

Verify /boot/grub2/grub.cfg Permissionsxccdf_org.ssgproject.content_rule_file_permissions_grub2_cfg medium

Verify /boot/grub2/grub.cfg Permissions

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_grub2_cfg
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6(7), 225, 1.5.2, Test attestation on 20121026 by DS

Description

File permissions for /boot/grub2/grub.cfg should be set to 600. To properly set the permissions of /boot/grub2/grub.cfg, run the command:

$ sudo chmod 600 /boot/grub2/grub.cfg

Rationale

Proper permissions ensure that only the root user can modify important boot parameters.

Set Boot Loader Passwordxccdf_org.ssgproject.content_rule_bootloader_password medium

Set Boot Loader Password

Rule IDxccdf_org.ssgproject.content_rule_bootloader_password
Result
notselected
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-2(1), IA-5(e), AC-3, 213, SRG-OS-000080-GPOS-00048, RHEL-07-010460, 1.5.3, Test attestation on 20121026 by DS

Description

The grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

To do so, select a superuser account and password and add them into the /etc/grub.d/01_users configuration file.

Since plaintext passwords are a security risk, generate a hash for the pasword by running the following command:

$ grub2-mkpasswd-pbkdf2
When prompted, enter the password that was selected and insert the returned password hash into the /etc/grub.d/01_users configuration file immediately after the superuser account. (Use the output from grub2-mkpasswd-pbkdf2 as the value of password-hash):
password_pbkdf2 superusers-account password-hash
NOTE: It is recommended not to use common administrator account names like root, admin, or administrator for the grub2 superuser account.

To meet FISMA Moderate, the bootloader superuser account and password MUST differ from the root account and password. Once the superuser account and password have been added, update the grub.cfg file by running:
grub2-mkconfig -o /boot/grub2/grub.cfg
NOTE: Do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.

Rationale

Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode. For more information on how to configure the grub2 superuser account and password, please refer to

  • https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/sec-GRUB_2_Password_Protection.html
  • .

Set the UEFI Boot Loader Passwordxccdf_org.ssgproject.content_rule_bootloader_uefi_password medium

Set the UEFI Boot Loader Password

Rule IDxccdf_org.ssgproject.content_rule_bootloader_uefi_password
Result
notselected
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  AC-3, 213, SRG-OS-000080-GPOS-00048, RHEL-07-010470

Description

The UEFI grub2 boot loader should have a superuser account and password protection enabled to protect boot-time settings.

To do so, select a superuser account and password and add them into the /etc/grub.d/01_users configuration file.

Since plaintext passwords are a security risk, generate a hash for the pasword by running the following command:

$ grub2-mkpasswd-pbkdf2
When prompted, enter the password that was selected and insert the returned password hash into the /etc/grub.d/01_users configuration file immediately after the superuser account. (Use the output from grub2-mkpasswd-pbkdf2 as the value of password-hash):
password_pbkdf2 superusers-account password-hash
NOTE: It is recommended not to use common administrator account names like root, admin, or administrator for the grub2 superuser account.

To meet FISMA Moderate, the bootloader superuser account and password MUST differ from the root account and password. Once the superuser account and password have been added, update the grub.cfg file by running:
grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
NOTE: Do NOT manually add the superuser account and password to the grub.cfg file as the grub2-mkconfig command overwrites this file.

Rationale

Password protection on the boot loader configuration ensures users with physical access cannot trivially alter important bootloader settings. These include which kernel to use, and whether to enter single-user mode. For more information on how to configure the grub2 superuser account and password, please refer to

  • https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/sec-GRUB_2_Password_Protection.html
  • .

Install the screen Packagexccdf_org.ssgproject.content_rule_package_screen_installed medium

Install the screen Package

Rule IDxccdf_org.ssgproject.content_rule_package_screen_installed
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-11(a), 57, SRG-OS-000029-GPOS-00010, RHEL-07-010072, Test attestation on 20121026 by DS

Description

To enable console screen locking, install the screen package:

$ sudo yum install screen
Instruct users to begin new terminal sessions with the following command:
$ screen
The console can now be locked with the following key combination:
ctrl+a x

Rationale

A session time-out lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but des not logout because of the temporary nature of the absence. Rather than relying on the user to manually lock their operation system session prior to vacating the vicinity, operating systems need to be able to identify when a user's session has idled and take action to initiate the session lock. The screen package allows for a session lock to be implemented and configured.

Enable Smart Card Loginxccdf_org.ssgproject.content_rule_smartcard_auth medium

Enable Smart Card Login

Rule IDxccdf_org.ssgproject.content_rule_smartcard_auth
Result
notselected
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  765, 766, 767, 768, 771, 772, 884, Req-8.3

Description

To enable smart card authentication, consult the documentation at:

  • https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7-Beta/html/System-Level_Authentication_Guide/authconfig-addl-auth.html#authconfig-smartcard
For guidance on enabling SSH to authenticate against a Common Access Card (CAC), consult documentation at:
  • https://access.redhat.com/solutions/82273

Rationale

Smart card login provides two-factor authentication stronger than that provided by a username and password combination. Smart cards leverage PKI (public key infrastructure) in order to provide and verify credentials.

Require Authentication for Single User Modexccdf_org.ssgproject.content_rule_require_singleuser_auth medium

Require Authentication for Single User Mode

Rule IDxccdf_org.ssgproject.content_rule_require_singleuser_auth
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

references:  IA-2(1), AC-3, 213, Test attestation on 20121024 by DS

Description

Single-user mode is intended as a system recovery method, providing a single user root access to the system by providing a boot option at startup. By default, no authentication is performed if single-user mode is selected.

By default, single-user mode is protected by requiring a password and is set in /usr/lib/systemd/system/rescue.service.

Rationale

This prevents attackers with physical access from trivially bypassing security on the machine and gaining root access. Such accesses are further prevented by configuring the bootloader password.

Disable debug-shell SystemD Servicexccdf_org.ssgproject.content_rule_service_debug-shell_disabled medium

Disable debug-shell SystemD Service

Rule IDxccdf_org.ssgproject.content_rule_service_debug-shell_disabled
Result
pass
Time2016-07-11T14:22:06
Severitymedium
Identifiers and References

identifiers: 

Description

SystemD's debug-shell service is intended to diagnose SystemD related boot issues with various systemctl commands. Once enabled and following a system reboot, the root shell will be available on tty9 which is access by pressing CTRL-ALT-F9. The debug-shell service should only be used for SystemD related issues and should otherwise be disabled.

By default, the debug-shell SystemD service is disabled. The debug-shell service can be disabled with the following command:

$ sudo systemctl disable debug-shell.service

Rationale

This prevents attackers with physical access from trivially bypassing security on the machine through valid troubleshooting configurations and gaining root access when the system is rebooted.

Disable Ctrl-Alt-Del Reboot Activationxccdf_org.ssgproject.content_rule_disable_ctrlaltdel_reboot high

Disable Ctrl-Alt-Del Reboot Activation

Rule IDxccdf_org.ssgproject.content_rule_disable_ctrlaltdel_reboot
Result
pass
Time2016-07-11T14:22:07
Severityhigh
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-020220

Description

By default, SystemD will reboot the system if the Ctrl-Alt-Del key sequence is pressed.
To configure the system to ignore the Ctrl-Alt-Del key sequence from the command line instead of rebooting the system, do either of the following:

ln -sf /dev/null /etc/systemd/system/ctrl-alt-del.target
or
systemctl mask ctrl-alt-del.target

Do not simply delete the /usr/lib/systemd/system/ctrl-alt-del.service file, as this file may be restored during future system updates.

Rationale

A locally logged-in user who presses Ctrl-Alt-Del, when at the console, can reboot the system. If accidentally pressed, as could happen in the case of mixed OS environment, this can create the risk of short-term loss of availability of systems due to unintentional reboot.

Warnings
warning  Disabling the Ctrl-Alt-Del key sequence with SystemD DOES NOT disable the Ctrl-Alt-Del key sequence if running in graphical.target mode (e.g. in GNOME, KDE, etc.)! The Ctrl-Alt-Del key sequence will only be disabled if running in the non-graphical multi-user.target mode.
Verify that Interactive Boot is Disabledxccdf_org.ssgproject.content_rule_disable_interactive_boot medium

Verify that Interactive Boot is Disabled

Rule IDxccdf_org.ssgproject.content_rule_disable_interactive_boot
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  SC-2, AC-3, 213, Test attestation on 20121024 by DS

Description

Red Hat Enterprise Linux systems support an "interactive boot" option that can be used to prevent services from being started. On a Red Hat Enterprise Linux 7 system, interactive boot can be enabled by providing a 1, yes, true, or on value to the systemd.confirm_spawn kernel argument in /etc/default/grub. Remove any instance of

systemd.confirm_spawn=(1|yes|true|on)
from the kernel arguments in that file to disable interactive boot.

Rationale

Using interactive boot, the console user could disable auditing, firewalls, or other services, weakening system security.

Warnings
warning  The GRUB 2 configuration file, grub.cfg, is automatically updated each time a new kernel is installed. Note that any changes to /etc/default/grub require rebuilding the grub.cfg file. To update the GRUB 2 configuration file manually, use the
grub2-mkconfig -o
command as follows:
  • On BIOS-based machines, issue the following command as root:
    ~]# grub2-mkconfig -o /boot/grub2/grub.cfg
  • On UEFI-based machines, issue the following command as root:
    ~]# grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
Enable GNOME3 Login Warning Bannerxccdf_org.ssgproject.content_rule_dconf_gnome_banner_enabled medium

Enable GNOME3 Login Warning Banner

Rule IDxccdf_org.ssgproject.content_rule_dconf_gnome_banner_enabled
Result
notselected
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-8(a), AC-8(b), AC-8(c)(1), AC-8(c)(2), AC-8(c)(3), 48, OS-SRG-000023-GPOS-00006, SRG-OS-000024-GPOS-00007, SRG-OS-000228-GPOS-00088, RHEL-07-010031

Description

To enable displaying a login warning banner in the GNOME Display Manager's login screen, the banner-message-enable setting must be set under an appropriate configuration file(s) in the /etc/dconf/db/gdm.d directory and locked in /etc/dconf/db/gdm.d/locks directory to prevent user modification. After the settings have been set, run dconf update. To display a banner, this setting must be enabled, and the user must be prevented from making changes. The banner text must also be set.

Rationale

Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. For U.S. Government systems, system use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.

Modify the System Login Bannerxccdf_org.ssgproject.content_rule_banner_etc_issue medium

Modify the System Login Banner

Rule IDxccdf_org.ssgproject.content_rule_banner_etc_issue
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-8(a), AC-8(b), AC-8(c)(1), AC-8(c)(2), AC-8(c)(3), 48, SRG-OS-000023-GPOS-00006, SRG-OS-000024-GPOS-00007, RHEL-07-010040, Test attestation on 20121026 by DS

Description

To configure the system login banner edit /etc/issue. Replace the default text with a message compliant with the local site policy or a legal disclaimer. The DoD required text is either:

You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:
-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.
-At any time, the USG may inspect and seize data stored on this IS.
-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.
-This IS includes security measures (e.g., authentication and access controls) to protect USG interests -- not for your personal benefit or privacy.
-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details.


OR:

I've read & consent to terms in IS user agreem't.

Rationale

Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via login interfaces with human users and are not required when such human interfaces do not exist.

Disable Kernel Parameter for Sending ICMP Redirects by Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_send_redirects medium

Disable Kernel Parameter for Sending ICMP Redirects by Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_send_redirects
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, SC-7, 1551, 4.1.2, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.default.send_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.default.send_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.default.send_redirects = 0

Rationale

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.
The ability to send ICMP redirects is only appropriate for systems acting as routers.

Disable Kernel Parameter for Sending ICMP Redirects for All Interfacesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_send_redirects medium

Disable Kernel Parameter for Sending ICMP Redirects for All Interfaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_send_redirects
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, SC-5(1), 1551, 4.1.2, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.all.send_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.all.send_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.all.send_redirects = 0

Rationale

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.
The ability to send ICMP redirects is only appropriate for systems acting as routers.

Disable Kernel Parameter for IP Forwardingxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_ip_forward medium

Disable Kernel Parameter for IP Forwarding

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_ip_forward
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, SC-5, 366, 4.1.1, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.ip_forward kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.ip_forward=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.ip_forward = 0

Rationale

IP forwarding permits the kernel to forward packets from one network interface to another. The ability to forward packets between two networks is only appropriate for systems acting as routers.

Configure Kernel Parameter for Accepting Source-Routed Packets for All Interfacesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_accept_source_route medium

Configure Kernel Parameter for Accepting Source-Routed Packets for All Interfaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_accept_source_route
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040350, 4.2.1, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.all.accept_source_route kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.all.accept_source_route=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.all.accept_source_route = 0

Rationale

Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv4 forwarding is enabled and the system is functioning as a router. Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required.

Configure Kernel Parameter for Accepting ICMP Redirects for All Interfacesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_accept_redirects medium

Configure Kernel Parameter for Accepting ICMP Redirects for All Interfaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_accept_redirects
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, SC-5, 1503, 1551, 4.2.2, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.all.accept_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.all.accept_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.all.accept_redirects = 0

Rationale

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless absolutely required.

Configure Kernel Parameter for Accepting Secure Redirects for All Interfacesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_secure_redirects medium

Configure Kernel Parameter for Accepting Secure Redirects for All Interfaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_secure_redirects
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, 1503, 1551, 4.2.3, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.all.secure_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.all.secure_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.all.secure_redirects = 0

Rationale

Accepting "secure" ICMP redirects (from those gateways listed as default gateways) has few legitimate uses. It should be disabled unless it is absolutely required.

Configure Kernel Parameter to Log Martian Packetsxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_log_martians low

Configure Kernel Parameter to Log Martian Packets

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_log_martians
Result
pass
Time2016-07-11T14:22:07
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), CM-7, SC-5(3), 126, 4.2.4, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.all.log_martians kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.all.log_martians=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.all.log_martians = 1

Rationale

The presence of "martian" packets (which have impossible addresses) as well as spoofed packets, source-routed packets, and redirects could be a sign of nefarious network activity. Logging these packets enables this activity to be detected.

Configure Kernel Parameter to Log Martian Packets By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_log_martians low

Configure Kernel Parameter to Log Martian Packets By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_log_martians
Result
pass
Time2016-07-11T14:22:07
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), CM-7, SC-5(3), 126, 4.2.4

Description

To set the runtime status of the net.ipv4.conf.default.log_martians kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.default.log_martians=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.default.log_martians = 1

Rationale

The presence of "martian" packets (which have impossible addresses) as well as spoofed packets, source-routed packets, and redirects could be a sign of nefarious network activity. Logging these packets enables this activity to be detected.

Configure Kernel Parameter for Accepting Source-Routed Packets By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_accept_source_route medium

Configure Kernel Parameter for Accepting Source-Routed Packets By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_accept_source_route
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, SC-7, 1551, SRG-OS-000480-GPOS-00227, RHEL-07-040350, 4.2.1, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.default.accept_source_route kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.default.accept_source_route=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.default.accept_source_route = 0

Rationale

Source-routed packates allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures.
Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It should be disabled unless it is absolutely required, such as when IPv4 forwarding is enabled and the system is legitimately functioning as a router.

Configure Kernel Parameter for Accepting ICMP Redirects By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_accept_redirects medium

Configure Kernel Parameter for Accepting ICMP Redirects By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_accept_redirects
Result
pass
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, SC-7, 1551, 4.2.2, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.default.accept_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.default.accept_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.default.accept_redirects = 0

Rationale

ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.
This feature of the IPv4 protocol has few legitimate uses. It should be disabled unless absolutely required.

Configure Kernel Parameter for Accepting Secure Redirects By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_secure_redirects medium

Configure Kernel Parameter for Accepting Secure Redirects By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_secure_redirects
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, SC-7, 1551, 4.2.3, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.default.secure_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.default.secure_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.default.secure_redirects = 0

Rationale

Accepting "secure" ICMP redirects (from those gateways listed as default gateways) has few legitimate uses. It should be disabled unless it is absolutely required.

Configure Kernel Parameter to Ignore ICMP Broadcast Echo Requestsxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_icmp_echo_ignore_broadcasts medium

Configure Kernel Parameter to Ignore ICMP Broadcast Echo Requests

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_icmp_echo_ignore_broadcasts
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, CM-7, SC-5, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040380, 4.2.5, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.icmp_echo_ignore_broadcasts kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.icmp_echo_ignore_broadcasts = 1

Rationale

Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks.
Ignoring ICMP echo requests (pings) sent to broadcast or multicast addresses makes the system slightly more difficult to enumerate on the network.

Configure Kernel Parameter to Ignore Bogus ICMP Error Responsesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_icmp_ignore_bogus_error_responses low

Configure Kernel Parameter to Ignore Bogus ICMP Error Responses

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_icmp_ignore_bogus_error_responses
Result
pass
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, SC-5, 4.2.6, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.icmp_ignore_bogus_error_responses kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.icmp_ignore_bogus_error_responses=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.icmp_ignore_bogus_error_responses = 1

Rationale

Ignoring bogus ICMP error responses reduces log size, although some activity would not be logged.

Configure Kernel Parameter to Use TCP Syncookiesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_tcp_syncookies medium

Configure Kernel Parameter to Use TCP Syncookies

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_tcp_syncookies
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, SC-5(1)(2), SC-5(2), SC-5(3), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040430, 4.2.8, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.tcp_syncookies kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.tcp_syncookies=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.tcp_syncookies = 1

Rationale

A TCP SYN flood attack can cause a denial of service by filling a system's TCP connection table with connections in the SYN_RCVD state. Syncookies can be used to track a connection when a subsequent ACK is received, verifying the initiator is attempting a valid connection and is not a flood source. This feature is activated when a flood condition is detected, and enables the system to continue servicing valid connection requests.

Configure Kernel Parameter to Use Reverse Path Filtering for All Interfacesxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_rp_filter medium

Configure Kernel Parameter to Use Reverse Path Filtering for All Interfaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_all_rp_filter
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, SC-5, SC-7, 1551, 4.2.7, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.all.rp_filter kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.all.rp_filter=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.all.rp_filter = 1

Rationale

Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems which are routers for complicated networks, but is helpful for end hosts and routers serving small networks.

Configure Kernel Parameter to Use Reverse Path Filtering by Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_rp_filter medium

Configure Kernel Parameter to Use Reverse Path Filtering by Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv4_conf_default_rp_filter
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, SC-5, SC-7, 4.2.7, Test attestation on 20121024 by DS

Description

To set the runtime status of the net.ipv4.conf.default.rp_filter kernel parameter, run the following command:

$ sudo sysctl -w net.ipv4.conf.default.rp_filter=1
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv4.conf.default.rp_filter = 1

Rationale

Enabling reverse path filtering drops packets with source addresses that should not have been able to be received on the interface they were received on. It should not be used on systems which are routers for complicated networks, but is helpful for end hosts and routers serving small networks.

Disable WiFi or Bluetooth in BIOSxccdf_org.ssgproject.content_rule_wireless_disable_in_bios low

Disable WiFi or Bluetooth in BIOS

Rule IDxccdf_org.ssgproject.content_rule_wireless_disable_in_bios
Result
notselected
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), AC-18(a), AC-18(d), AC-18(3), CM-7, 85

Description

Some systems that include built-in wireless support offer the ability to disable the device through the BIOS. This is system-specific; consult your hardware manual or explore the BIOS setup during boot.

Rationale

Disabling wireless support in the BIOS prevents easy activation of the wireless interface, generally requiring administrators to reboot the system first.

Deactivate Wireless Network Interfacesxccdf_org.ssgproject.content_rule_wireless_disable_interfaces low

Deactivate Wireless Network Interfaces

Rule IDxccdf_org.ssgproject.content_rule_wireless_disable_interfaces
Result
notselected
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), AC-18(a), AC-18(d), AC-18(3), CM-7, 85, 4.3.1, Test attestation on 20121025 by DS

Description

Deactivating wireless network interfaces should prevent normal usage of the wireless capability.

First, identify the interfaces available with the command:

$ ifconfig -a
Additionally, the following command may be used to determine whether wireless support is included for a particular interface, though this may not always be a clear indicator:
$ iwconfig
After identifying any wireless interfaces (which may have names like wlan0, ath0, wifi0, em1 or eth0), deactivate the interface with the command:
$ sudo ifdown interface
These changes will only last until the next reboot. To disable the interface for future boots, remove the appropriate interface file from /etc/sysconfig/network-scripts:
$ sudo rm /etc/sysconfig/network-scripts/ifcfg-interface

Rationale

Wireless networking allows attackers within physical proximity to launch network-based attacks against systems, including those against local LAN protocols which were not designed with security in mind.

Disable Bluetooth Servicexccdf_org.ssgproject.content_rule_service_bluetooth_disabled medium

Disable Bluetooth Service

Rule IDxccdf_org.ssgproject.content_rule_service_bluetooth_disabled
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8), AC-18(a), AC-18(d), AC-18(3), CM-7, 85, 1551, Test attestation on 20121025 by DS

Description

The bluetooth service can be disabled with the following command:

$ sudo systemctl disable bluetooth.service
$ sudo service bluetooth stop

Rationale

Disabling the bluetooth service prevents the system from attempting connections to Bluetooth devices, which entails some security risk. Nevertheless, variation in this risk decision may be expected due to the utility of Bluetooth connectivity and its limited range.

Disable Bluetooth Kernel Modulesxccdf_org.ssgproject.content_rule_kernel_module_bluetooth_disabled medium

Disable Bluetooth Kernel Modules

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_bluetooth_disabled
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8), AC-18(a), AC-18(d), AC-18(3), CM-7, 85, 1551, Test attestation on 20141031 by JL

Description

The kernel's module loading system can be configured to prevent loading of the Bluetooth module. Add the following to the appropriate /etc/modprobe.d configuration file to prevent the loading of the Bluetooth module:

install bluetooth /bin/true

Rationale

If Bluetooth functionality must be disabled, preventing the kernel from loading the kernel module provides an additional safeguard against its activation.

Disable IPv6 Networking Support Automatic Loadingxccdf_org.ssgproject.content_rule_sysctl_kernel_ipv6_disable medium

Disable IPv6 Networking Support Automatic Loading

Rule IDxccdf_org.ssgproject.content_rule_sysctl_kernel_ipv6_disable
Result
notselected
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 1551, 4.4.2, Test attestation on 20121024 by DS

Description

To disable support for (ipv6) add the following line to /etc/sysctl.d/ipv6.conf (or another file in /etc/sysctl.d):

net.ipv6.conf.all.disable_ipv6 = 1
This disables IPv6 on all network interfaces as other services and system functionality require the IPv6 stack loaded to work.

Rationale

Any unnecessary network stacks - including IPv6 - should be disabled, to reduce the vulnerability to exploitation.

Disable Interface Usage of IPv6xccdf_org.ssgproject.content_rule_network_ipv6_disable_interfaces low

Disable Interface Usage of IPv6

Rule IDxccdf_org.ssgproject.content_rule_network_ipv6_disable_interfaces
Result
notselected
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

Description

To disable interface usage of IPv6, add or correct the following lines in /etc/sysconfig/network:

NETWORKING_IPV6=no
IPV6INIT=no

Disable Support for RPC IPv6xccdf_org.ssgproject.content_rule_network_ipv6_disable_rpc low

Disable Support for RPC IPv6

Rule IDxccdf_org.ssgproject.content_rule_network_ipv6_disable_rpc
Result
notselected
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

RPC services for NFSv4 try to load transport modules for udp6 and tcp6 by default, even if IPv6 has been disabled in /etc/modprobe.d. To prevent RPC services such as rpc.mountd from attempting to start IPv6 network listeners, remove or comment out the following two lines in /etc/netconfig:

udp6       tpi_clts      v     inet6    udp     -       -
tcp6       tpi_cots_ord  v     inet6    tcp     -       -

Configure Kernel Parameter for Accepting Source-Routed Packets for All Interfacesxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_source_route medium

Configure Kernel Parameter for Accepting Source-Routed Packets for All Interfaces

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_source_route
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040860

Description

To set the runtime status of the net.ipv6.conf.all.accept_source_route kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.all.accept_source_route=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.all.accept_source_route = 0

Rationale

Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router. Accepting source-routed packets in the IPv6 protocol has few legitimate uses. It should be disabled unless it is absolutely required.

Configure Accepting IPv6 Router Advertisementsxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_ra low

Configure Accepting IPv6 Router Advertisements

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_ra
Result
pass
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 4.4.1.1

Description

To set the runtime status of the net.ipv6.conf.all.accept_ra kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.all.accept_ra=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.all.accept_ra = 0

Rationale

An illicit router advertisement message could result in a man-in-the-middle attack.

Configure Accepting IPv6 Router Advertisementsxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_ra low

Configure Accepting IPv6 Router Advertisements

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_ra
Result
pass
Time2016-07-11T14:22:08
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 4.4.1.1

Description

To set the runtime status of the net.ipv6.conf.default.accept_ra kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.default.accept_ra=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.default.accept_ra = 0

Rationale

An illicit router advertisement message could result in a man-in-the-middle attack.

Configure Accepting IPv6 Redirects By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_redirects medium

Configure Accepting IPv6 Redirects By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_accept_redirects
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 1551, 4.4.1.2

Description

To set the runtime status of the net.ipv6.conf.all.accept_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.all.accept_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.all.accept_redirects = 0

Rationale

An illicit ICMP redirect message could result in a man-in-the-middle attack.

Configure Accepting IPv6 Redirects By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_redirects medium

Configure Accepting IPv6 Redirects By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_redirects
Result
pass
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 1551, 4.4.1.2

Description

To set the runtime status of the net.ipv6.conf.default.accept_redirects kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.default.accept_redirects=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.default.accept_redirects = 0

Rationale

An illicit ICMP redirect message could result in a man-in-the-middle attack.

Configure Kernel Parameter for Accepting Source-Routed Packets for Interfaces By Defaultxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_source_route medium

Configure Kernel Parameter for Accepting Source-Routed Packets for Interfaces By Default

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_default_accept_source_route
Result
fail
Time2016-07-11T14:22:08
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, 366

Description

To set the runtime status of the net.ipv6.conf.default.accept_source_route kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.default.accept_source_route=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.default.accept_source_route = 0

Rationale

Source-routed packets allow the source of the packet to suggest routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routerd traffic, such as when IPv6 forwarding is enabled and the system is functioning as a router. Accepting source-routed packets in the IPv6 protocol has few legitimate uses. It should be disabled unless it is absolutely required.

Disable Kernel Parameter for IPv6 Forwardingxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_forwarding medium

Disable Kernel Parameter for IPv6 Forwarding

Rule IDxccdf_org.ssgproject.content_rule_sysctl_net_ipv6_conf_all_forwarding
Result
fail
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, SC-5, 366, 4.1.1

Description

To set the runtime status of the net.ipv6.conf.all.forwarding kernel parameter, run the following command:

$ sudo sysctl -w net.ipv6.conf.all.forwarding=0
If this is not the system's default value, add the following line to /etc/sysctl.conf:
net.ipv6.conf.all.forwarding = 0

Rationale

IP forwarding permits the kernel to forward packets from one network interface to another. The ability to forward packets between two networks is only appropriate for systems acting as routers.

Manually Assign Global IPv6 Addressxccdf_org.ssgproject.content_rule_network_ipv6_static_address low

Manually Assign Global IPv6 Address

Rule IDxccdf_org.ssgproject.content_rule_network_ipv6_static_address
Result
fail
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  366

Description

To manually assign an IP address for an interface, edit the file /etc/sysconfig/network-scripts/ifcfg-interface. Add or correct the following line (substituting the correct IPv6 address):

IPV6ADDR=2001:0DB8::ABCD/64
Manually assigning an IP address is preferable to accepting one from routers or from the network otherwise. The example address here is an IPv6 address reserved for documentation purposes, as defined by RFC3849.

Use Privacy Extensions for Addressxccdf_org.ssgproject.content_rule_network_ipv6_privacy_extensions low

Use Privacy Extensions for Address

Rule IDxccdf_org.ssgproject.content_rule_network_ipv6_privacy_extensions
Result
fail
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  366

Description

To introduce randomness into the automatic generation of IPv6 addresses, add or correct the following line in /etc/sysconfig/network-scripts/ifcfg-interface:

IPV6_PRIVACY=rfc3041
Automatically-generated IPv6 addresses are based on the underlying hardware (e.g. Ethernet) address, and so it becomes possible to track a piece of hardware over its lifetime using its traffic. If it is important for a system's IP address to not trivially reveal its hardware address, this setting should be applied.

Manually Assign IPv6 Router Addressxccdf_org.ssgproject.content_rule_network_ipv6_default_gateway low

Manually Assign IPv6 Router Address

Rule IDxccdf_org.ssgproject.content_rule_network_ipv6_default_gateway
Result
fail
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  366

Description

Edit the file /etc/sysconfig/network-scripts/ifcfg-interface, and add or correct the following line (substituting your gateway IP as appropriate):

IPV6_DEFAULTGW=2001:0DB8::0001
Router addresses should be manually set and not accepted via any auto-configuration or router advertisement.

Verify firewalld Enabledxccdf_org.ssgproject.content_rule_service_firewalld_enabled medium

Verify firewalld Enabled

Rule IDxccdf_org.ssgproject.content_rule_service_firewalld_enabled
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(b), 366, 4.7, SRG-OS-000480-GPOS-00227, RHEL-07-040810

Description

The firewalld service can be enabled with the following command:

$ sudo systemctl enable firewalld.service

Rationale

Access control methods provide the ability to enhance system security posture by restricting services and known good IP addresses and address ranges. This prevents connections from unknown hosts and protocols.

Set Default firewalld Zone for Incoming Packetsxccdf_org.ssgproject.content_rule_set_firewalld_default_zone medium

Set Default firewalld Zone for Incoming Packets

Rule IDxccdf_org.ssgproject.content_rule_set_firewalld_default_zone
Result
notselected
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 66, 1109, 1154, 1414

Description

To set the default zone to drop for the built-in default zone which processes incoming IPv4 and IPv6 packets, modify the following line in /etc/firewalld/firewalld.conf to be:

DefaultZone=drop

Rationale

In firewalld the default zone is applied only after all the applicable rules in the table are examined for a match. Setting the default zone to drop implements proper design for a firewall, i.e. any packets which are not explicitly permitted should not be accepted.

Disable DCCP Supportxccdf_org.ssgproject.content_rule_kernel_module_dccp_disabled medium

Disable DCCP Support

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_dccp_disabled
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, http://iase.disa.mil/stigs/cci/Pages/index.aspx, 4.6.1, Test attestation on 20121024 by DS

Description

The Datagram Congestion Control Protocol (DCCP) is a relatively new transport layer protocol, designed to support streaming media and telephony. To configure the system to prevent the dccp kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install dccp /bin/true

Rationale

Disabling DCCP protects the system against exploitation of any flaws in its implementation.

Disable SCTP Supportxccdf_org.ssgproject.content_rule_kernel_module_sctp_disabled medium

Disable SCTP Support

Rule IDxccdf_org.ssgproject.content_rule_kernel_module_sctp_disabled
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, http://iase.disa.mil/stigs/cci/Pages/index.aspx, 4.6.2, Test attestation on 20121024 by DS

Description

The Stream Control Transmission Protocol (SCTP) is a transport layer protocol, designed to support the idea of message-oriented communication, with several streams of messages within one connection. To configure the system to prevent the sctp kernel module from being loaded, add the following line to a file in the directory /etc/modprobe.d:

install sctp /bin/true

Rationale

Disabling SCTP protects the system against exploitation of any flaws in its implementation.

Install libreswan Packagexccdf_org.ssgproject.content_rule_package_libreswan_installed medium

Install libreswan Package

Rule IDxccdf_org.ssgproject.content_rule_package_libreswan_installed
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17, MA-4, SC-9, 1130, 1131, Req-4.1

Description

The Libreswan package provides an implementation of IPsec and IKE, which permits the creation of secure tunnels over untrusted networks. The libreswan package can be installed with the following command:

$ sudo yum install libreswan

Rationale

Providing the ability for remote users or systems to initiate a secure VPN connection protects information when it is transmitted over a wide area network.

Verify Any Configured IPSec Tunnel Connectionsxccdf_org.ssgproject.content_rule_libreswan_approved_tunnels medium

Verify Any Configured IPSec Tunnel Connections

Rule IDxccdf_org.ssgproject.content_rule_libreswan_approved_tunnels
Result
notchecked
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-4, 336, SRG-OS-000480-GPOS-00227, RHEL-07-040830

Description

Libreswan provides an implementation of IPsec and IKE, which permits the creation of secure tunnels over untrusted networks. As such, IPsec can be used to circumvent certain network requirements such as filtering. Verify that if any IPsec connection (conn) configured in /etc/ipsec.conf and /etc/ipsec.d exists is an approved organizational connection.

Rationale

IP tunneling mechanisms can be used to bypass network filtering.

Evaluation messages
info 
No candidate or applicable check found.
Disable Client Dynamic DNS Updatesxccdf_org.ssgproject.content_rule_network_disable_ddns_interfaces medium

Disable Client Dynamic DNS Updates

Rule IDxccdf_org.ssgproject.content_rule_network_disable_ddns_interfaces
Result
notselected
Time2016-07-11T14:22:07
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040840

Description

Dynamic DNS allows clients to dynamically update their own DNS records. The updates are transmitted by unencrypted means which can reveal information to a potential malicious user. If the system does not require Dynamic DNS, remove all DHCP_HOSTNAME references from the /etc/sysconfig/network-scripts/ifcfg-interface scripts. If dhclient is used, remove all send host-name hostname references from the /etc/dhclient.conf configuration file and/or any reference from the /etc/dhcp directory.

Rationale

Dynamic DNS updates transmit unencrypted information about a system including its name and address and should not be used unless needed.

Disable Zeroconf Networkingxccdf_org.ssgproject.content_rule_network_disable_zeroconf low

Disable Zeroconf Networking

Rule IDxccdf_org.ssgproject.content_rule_network_disable_zeroconf
Result
pass
Time2016-07-11T14:22:07
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Zeroconf networking allows the system to assign itself an IP address and engage in IP communication without a statically-assigned address or even a DHCP server. Automatic address assignment via Zeroconf (or DHCP) is not recommended. To disable Zeroconf automatic route assignment in the 169.254.0.0 subnet, add or correct the following line in /etc/sysconfig/network:

NOZEROCONF=yes

Rationale

Zeroconf addresses are in the network 169.254.0.0. The networking scripts add entries to the system's routing table for these addresses. Zeroconf address assignment commonly occurs when the system is configured to use DHCP but fails to receive an address assignment from the DHCP server.

Ensure System is Not Acting as a Network Snifferxccdf_org.ssgproject.content_rule_network_sniffer_disabled low

Ensure System is Not Acting as a Network Sniffer

Rule IDxccdf_org.ssgproject.content_rule_network_sniffer_disabled
Result
pass
Time2016-07-11T14:22:07
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, MA-3

Description

The system should not be acting as a network sniffer, which can capture all traffic on the network to which it is connected. Run the following to determine if any interface is running in promiscuous mode:

$ ip link | grep PROMISC

Rationale

If any results are returned, then a sniffing process (such as tcpdump or Wireshark) is likely to be using the interface and this should be investigated.

Ensure Log Files Are Owned By Appropriate Userxccdf_org.ssgproject.content_rule_rsyslog_files_ownership medium

Ensure Log Files Are Owned By Appropriate User

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_files_ownership
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, SI-11, 1314, Req-10.5.1, Req-10.5.2, Test attestation on 20121024 by DS

Description

The owner of all log files written by rsyslog should be root. These log files are determined by the second part of each Rule line in /etc/rsyslog.conf and typically all appear in /var/log. For each log file LOGFILE referenced in /etc/rsyslog.conf, run the following command to inspect the file's owner:

$ ls -l LOGFILE
If the owner is not root, run the following command to correct this:
$ sudo chown root LOGFILE

Rationale

The log files generated by rsyslog contain valuable information regarding system configuration, user authentication, and other such information. Log files should be protected from unauthorized access.

Ensure Log Files Are Owned By Appropriate Groupxccdf_org.ssgproject.content_rule_rsyslog_files_groupownership medium

Ensure Log Files Are Owned By Appropriate Group

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_files_groupownership
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, SI-11, 1314, Req-10.5.1, Req-10.5.2, Test attestation on 20121024 by DS

Description

The group-owner of all log files written by rsyslog should be root. These log files are determined by the second part of each Rule line in /etc/rsyslog.conf and typically all appear in /var/log. For each log file LOGFILE referenced in /etc/rsyslog.conf, run the following command to inspect the file's group owner:

$ ls -l LOGFILE
If the owner is not root, run the following command to correct this:
$ sudo chgrp root LOGFILE

Rationale

The log files generated by rsyslog contain valuable information regarding system configuration, user authentication, and other such information. Log files should be protected from unauthorized access.

Ensure System Log Files Have Correct Permissionsxccdf_org.ssgproject.content_rule_rsyslog_files_permissions medium

Ensure System Log Files Have Correct Permissions

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_files_permissions
Result
fixed
Time2016-07-11T14:24:56
Severitymedium
Identifiers and References

identifiers: 

references:  SI-11, 1314, Req-10.5.1, Req-10.5.2, 5.1.4, Test attestation on 20121024 by DS

Description

The file permissions for all log files written by rsyslog should be set to 600, or more restrictive. These log files are determined by the second part of each Rule line in /etc/rsyslog.conf and typically all appear in /var/log. For each log file LOGFILE referenced in /etc/rsyslog.conf, run the following command to inspect the file's permissions:

$ ls -l LOGFILE
If the permissions are not 600 or more restrictive, run the following command to correct this:
$ sudo chmod 0600 LOGFILE

Rationale

Log files can contain valuable information regarding system configuration. If the system log files are not protected unauthorized users could change the logged data, eliminating their forensic value.

Evaluation messages
info 
Fix execution completed and returned: 0
Ensure Logs Sent To Remote Hostxccdf_org.ssgproject.content_rule_rsyslog_remote_loghost low

Ensure Logs Sent To Remote Host

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_remote_loghost
Result
notselected
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AU-3(2), AU-4(1), AU-9, 1348, 136, 1851, 5.1.5

Description

To configure rsyslog to send logs to a remote log server, open /etc/rsyslog.conf and read and understand the last section of the file, which describes the multiple directives necessary to activate remote logging. Along with these other directives, the system can be configured to forward its logs to a particular log server by adding or correcting one of the following lines, substituting loghost.example.com appropriately. The choice of protocol depends on the environment of the system; although TCP and RELP provide more reliable message delivery, they may not be supported in all environments.
To use UDP for log message delivery:

*.* @loghost.example.com

To use TCP for log message delivery:
*.* @@loghost.example.com

To use RELP for log message delivery:
*.* :omrelp:loghost.example.com

Rationale

A log server (loghost) receives syslog messages from one or more systems. This data can be used as an additional log source in the event a system is compromised and its local logs are suspect. Forwarding log messages to a remote loghost also provides system administrators with a centralized place to view the status of multiple hosts within the enterprise.

Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Serverxccdf_org.ssgproject.content_rule_rsyslog_nolisten low

Ensure rsyslog Does Not Accept Remote Messages Unless Acting As Log Server

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_nolisten
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AU-9(2), AC-4

Description

The rsyslog daemon should not accept remote messages unless the system acts as a log server. To ensure that it is not listening on the network, ensure the following lines are not found in /etc/rsyslog.conf:

$ModLoad imtcp
$InputTCPServerRun port
$ModLoad imudp
$UDPServerRun port
$ModLoad imrelp
$InputRELPServerRun port

Rationale

Any process which receives messages from the network incurs some risk of receiving malicious messages. This risk can be eliminated for rsyslog by configuring it not to listen on the network.

Enable rsyslog to Accept Messages via TCP, if Acting As Log Serverxccdf_org.ssgproject.content_rule_rsyslog_accept_remote_messages_tcp low

Enable rsyslog to Accept Messages via TCP, if Acting As Log Server

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_accept_remote_messages_tcp
Result
notchecked
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AU-9, 5.1.6

Description

The rsyslog daemon should not accept remote messages unless the system acts as a log server. If the system needs to act as a central log server, add the following lines to /etc/rsyslog.conf to enable reception of messages over TCP:

$ModLoad imtcp
$InputTCPServerRun 514

Rationale

If the system needs to act as a log server, this ensures that it can receive messages over a reliable TCP connection.

Evaluation messages
info 
No candidate or applicable check found.
Enable rsyslog to Accept Messages via UDP, if Acting As Log Serverxccdf_org.ssgproject.content_rule_rsyslog_accept_remote_messages_udp low

Enable rsyslog to Accept Messages via UDP, if Acting As Log Server

Rule IDxccdf_org.ssgproject.content_rule_rsyslog_accept_remote_messages_udp
Result
notchecked
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AU-9, 5.1.6

Description

The rsyslog daemon should not accept remote messages unless the system acts as a log server. If the system needs to act as a central log server, add the following lines to /etc/rsyslog.conf to enable reception of messages over UDP:

$ModLoad imudp
$UDPServerRun 514

Rationale

Many devices, such as switches, routers, and other Unix-like systems, may only support the traditional syslog transmission over UDP. If the system must act as a log server, this enables it to receive their messages as well.

Evaluation messages
info 
No candidate or applicable check found.
Ensure Logrotate Runs Periodicallyxccdf_org.ssgproject.content_rule_ensure_logrotate_activated low

Ensure Logrotate Runs Periodically

Rule IDxccdf_org.ssgproject.content_rule_ensure_logrotate_activated
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AU-9, 366, Req-10.7

Description

The logrotate utility allows for the automatic rotation of log files. The frequency of rotation is specified in /etc/logrotate.conf, which triggers a cron task. To configure logrotate to run daily, add or correct the following line in /etc/logrotate.conf:

# rotate log files frequency
daily

Rationale

Log files that are not properly rotated run the risk of growing so large that they fill up the /var/log partition. Valuable logging information could be lost if the /var/log partition becomes full.

Configure Logwatch HostLimit Linexccdf_org.ssgproject.content_rule_logwatch_configured_hostlimit low

Configure Logwatch HostLimit Line

Rule IDxccdf_org.ssgproject.content_rule_logwatch_configured_hostlimit
Result
notselected
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

Description

On a central logserver, you want Logwatch to summarize all syslog entries, including those which did not originate on the logserver itself. The HostLimit setting tells Logwatch to report on all hosts, not just the one on which it is running.

 HostLimit = no 

Configure Logwatch SplitHosts Linexccdf_org.ssgproject.content_rule_logwatch_configured_splithosts low

Configure Logwatch SplitHosts Line

Rule IDxccdf_org.ssgproject.content_rule_logwatch_configured_splithosts
Result
notselected
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

Description

If SplitHosts is set, Logwatch will separate entries by hostname. This makes the report longer but significantly more usable. If it is not set, then Logwatch will not report which host generated a given log entry, and that information is almost always necessary

 SplitHosts = yes 

Ensure rsyslog is Installedxccdf_org.ssgproject.content_rule_package_rsyslog_installed medium

Ensure rsyslog is Installed

Rule IDxccdf_org.ssgproject.content_rule_package_rsyslog_installed
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-9(2), 1311, 1312, 5.1.1, Test attestation on 20121024 by DS

Description

Rsyslog is installed by default. The rsyslog package can be installed with the following command:

$ sudo yum install rsyslog

Rationale

The rsyslog package provides the rsyslog daemon, which provides system logging services.

Enable rsyslog Servicexccdf_org.ssgproject.content_rule_service_rsyslog_enabled medium

Enable rsyslog Service

Rule IDxccdf_org.ssgproject.content_rule_service_rsyslog_enabled
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-4(1), AU-12, 1311, 1312, 1557, 1851, 5.1.2, Test attestation on 20121024 by DS

Description

The rsyslog service provides syslog-style logging by default on Red Hat Enterprise Linux 7. The rsyslog service can be enabled with the following command:

$ sudo systemctl enable rsyslog.service

Rationale

The rsyslog service must be running in order to provide logging services, which are essential to system administration.

Disable Logwatch on Clients if a Logserver Existsxccdf_org.ssgproject.content_rule_disable_logwatch_for_logserver low

Disable Logwatch on Clients if a Logserver Exists

Rule IDxccdf_org.ssgproject.content_rule_disable_logwatch_for_logserver
Result
notchecked
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

Description

Does your site have a central logserver which has been configured to report on logs received from all systems? If so:

 
$ sudo rm /etc/cron.daily/0logwatch 
If no logserver exists, it will be necessary for each machine to run Logwatch individually. Using a central logserver provides the security and reliability benefits discussed earlier, and also makes monitoring logs easier and less time-intensive for administrators.

Evaluation messages
info 
No candidate or applicable check found.
Configure auditd Number of Logs Retainedxccdf_org.ssgproject.content_rule_auditd_data_retention_num_logs medium

Configure auditd Number of Logs Retained

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_num_logs
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-11, IR-5, Req-10.7, Test attestation on 20121024 by DS

Description

Determine how many log files auditd should retain when it rotates logs. Edit the file /etc/audit/auditd.conf. Add or modify the following line, substituting NUMLOGS with the correct value of 5:

num_logs = NUMLOGS
Set the value to 5 for general-purpose systems. Note that values less than 2 result in no log rotation.

Rationale

The total storage for audit log files must be large enough to retain log information over the period required. This is a function of the maximum log file size and the number of logs retained.

Configure auditd Max Log File Sizexccdf_org.ssgproject.content_rule_auditd_data_retention_max_log_file medium

Configure auditd Max Log File Size

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_max_log_file
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-11, IR-5, Req-10.7, 5.2.1.1, Test attestation on 20121024 by DS

Description

Determine the amount of audit data (in megabytes) which should be retained in each log file. Edit the file /etc/audit/auditd.conf. Add or modify the following line, substituting the correct value of 6 for STOREMB:

max_log_file = STOREMB
Set the value to 6 (MB) or higher for general-purpose systems. Larger values, of course, support retention of even more audit data.

Rationale

The total storage for audit log files must be large enough to retain log information over the period required. This is a function of the maximum log file size and the number of logs retained.

Configure auditd max_log_file_action Upon Reaching Maximum Log Sizexccdf_org.ssgproject.content_rule_auditd_data_retention_max_log_file_action medium

Configure auditd max_log_file_action Upon Reaching Maximum Log Size

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_max_log_file_action
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-4, AU-11, IR-5, Req-10.7, 5.2.1.3, Test attestation on 20121024 by DS

Description

The default action to take when the logs reach their maximum size is to rotate the log files, discarding the oldest one. To configure the action taken by auditd, add or correct the line in /etc/audit/auditd.conf:

max_log_file_action = ACTION
Possible values for ACTION are described in the auditd.conf man page. These include:
  • ignore
  • syslog
  • suspend
  • rotate
  • keep_logs
Set the ACTION to rotate to ensure log rotation occurs. This is the default. The setting is case-insensitive.

Rationale

Automatically rotating logs (by setting this to rotate) minimizes the chances of the system unexpectedly running out of disk space by being overwhelmed with log data. However, for systems that must never discard log data, or which use external processes to transfer it and reclaim space, keep_logs can be employed.

Configure auditd space_left Action on Low Disk Spacexccdf_org.ssgproject.content_rule_auditd_data_retention_space_left_action medium

Configure auditd space_left Action on Low Disk Space

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_space_left_action
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-4, AU-5(b), IR-5, 140, 143, Req-10.7, 5.2.1.2, Test attestation on 20121024 by DS

Description

The auditd service can be configured to take an action when disk space starts to run low. Edit the file /etc/audit/auditd.conf. Modify the following line, substituting ACTION appropriately:

space_left_action = ACTION
Possible values for ACTION are described in the auditd.conf man page. These include:
  • ignore
  • syslog
  • email
  • exec
  • suspend
  • single
  • halt
Set this to email (instead of the default, which is suspend) as it is more likely to get prompt attention. Acceptable values also include suspend, single, and halt.

Rationale

Notifying administrators of an impending disk space problem may allow them to take corrective action prior to any disruption.

Configure auditd admin_space_left Action on Low Disk Spacexccdf_org.ssgproject.content_rule_auditd_data_retention_admin_space_left_action medium

Configure auditd admin_space_left Action on Low Disk Space

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_admin_space_left_action
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-4, AU-5(b), IR-5, 140, 1343, Req-10.7, 5.2.1.2, Test attestation on 20121024 by DS

Description

The auditd service can be configured to take an action when disk space is running low but prior to running out of space completely. Edit the file /etc/audit/auditd.conf. Add or modify the following line, substituting ACTION appropriately:

admin_space_left_action = ACTION
Set this value to single to cause the system to switch to single user mode for corrective action. Acceptable values also include suspend and halt. For certain systems, the need for availability outweighs the need to log all actions, and a different setting should be determined. Details regarding all possible values for ACTION are described in the auditd.conf man page.

Rationale

Administrators should be made aware of an inability to record audit records. If a separate partition or logical volume of adequate size is used, running low on space for audit records should never occur.

Configure auditd mail_acct Action on Low Disk Spacexccdf_org.ssgproject.content_rule_auditd_data_retention_action_mail_acct medium

Configure auditd mail_acct Action on Low Disk Space

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_action_mail_acct
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-4, AU-5(a), IR-5, 139, 144, Req-10.7.a, 5.2.1.2

Description

The auditd service can be configured to send email to a designated account in certain situations. Add or correct the following line in /etc/audit/auditd.conf to ensure that administrators are notified via email for those situations:

action_mail_acct = root

Rationale

Email sent to the root account is typically aliased to the administrators of the system, who can take appropriate action.

Configure auditd flush priorityxccdf_org.ssgproject.content_rule_auditd_data_retention_flush low

Configure auditd flush priority

Rule IDxccdf_org.ssgproject.content_rule_auditd_data_retention_flush
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AU-9, AU-12(1), 1576

Description

The auditd service can be configured to synchronously write audit event data to disk. Add or correct the following line in /etc/audit/auditd.conf to ensure that audit event data is fully synchronized with the log files on the disk:

flush = data

Rationale

Audit data should be synchronously written to disk to ensure log integrity. These parameters assure that all audit event data is fully synchronized with the log files on the disk.

Configure auditd to use audispd's syslog pluginxccdf_org.ssgproject.content_rule_auditd_audispd_syslog_plugin_activated medium

Configure auditd to use audispd's syslog plugin

Rule IDxccdf_org.ssgproject.content_rule_auditd_audispd_syslog_plugin_activated
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-1(b), AU-3(2), IR-5, 136, Req-10.5.3

Description

To configure the auditd service to use the syslog plug-in of the audispd audit event multiplexor, set the active line in /etc/audisp/plugins.d/syslog.conf to yes. Restart the auditd service:

$ sudo service auditd restart

Rationale

The auditd service does not include the ability to send audit records to a centralized server for management directly. It does, however, include a plug-in for audit event multiplexor (audispd) to pass audit records to the local syslog server

Record attempts to alter time through adjtimexxccdf_org.ssgproject.content_rule_audit_rules_time_adjtimex low

Record attempts to alter time through adjtimex

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_time_adjtimex
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 5.2.4, Req-10.4.2.b, 1487, 169

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S adjtimex -k audit_time_rules
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S adjtimex -k audit_time_rules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S adjtimex -k audit_time_rules
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S adjtimex -k audit_time_rules
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined syscalls:
-a always,exit -F arch=b64 -S adjtimex -S settimeofday -k audit_time_rules

Rationale

Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.

Record attempts to alter time through settimeofdayxccdf_org.ssgproject.content_rule_audit_rules_time_settimeofday low

Record attempts to alter time through settimeofday

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_time_settimeofday
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 5.2.4, Req-10.4.2.b, 1487, 169

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S settimeofday -k audit_time_rules
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S settimeofday -k audit_time_rules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S settimeofday -k audit_time_rules
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S settimeofday -k audit_time_rules
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined syscalls:
-a always,exit -F arch=b64 -S adjtimex -S settimeofday -k audit_time_rules

Rationale

Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.

Record Attempts to Alter Time Through stimexccdf_org.ssgproject.content_rule_audit_rules_time_stime low

Record Attempts to Alter Time Through stime

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_time_stime
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, Req-10.4.2.b, 1487, 169

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d for both 32 bit and 64 bit systems:

-a always,exit -F arch=b32 -S stime -k audit_time_rules
Since the 64 bit version of the "stime" system call is not defined in the audit lookup table, the corresponding "-F arch=b64" form of this rule is not expected to be defined on 64 bit systems (the aforementioned "-F arch=b32" stime rule form itself is sufficient for both 32 bit and 64 bit systems). If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file for both 32 bit and 64 bit systems:
-a always,exit -F arch=b32 -S stime -k audit_time_rules
Since the 64 bit version of the "stime" system call is not defined in the audit lookup table, the corresponding "-F arch=b64" form of this rule is not expected to be defined on 64 bit systems (the aforementioned "-F arch=b32" stime rule form itself is sufficient for both 32 bit and 64 bit systems). The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined system calls:
-a always,exit -F arch=b64 -S adjtimex -S settimeofday -k audit_time_rules

Rationale

Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.

Record Attempts to Alter Time Through clock_settimexccdf_org.ssgproject.content_rule_audit_rules_time_clock_settime low

Record Attempts to Alter Time Through clock_settime

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_time_clock_settime
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 5.2.4, Req-10.4.2.b, 1487, 169

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S clock_settime -F a0=0x0 -F key=time-change
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S clock_settime -F a0=0x0 -F key=time-change
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S clock_settime -F a0=0x0 -F key=time-change
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S clock_settime -F a0=0x0 -F key=time-change
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport. Multiple system calls can be defined on the same line to save space if desired, but is not required. See an example of multiple combined syscalls:
-a always,exit -F arch=b64 -S adjtimex -S settimeofday -k audit_time_rules

Rationale

Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.

Record Attempts to Alter the localtime Filexccdf_org.ssgproject.content_rule_audit_rules_time_watch_localtime low

Record Attempts to Alter the localtime File

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_time_watch_localtime
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(b), IR-5, 5.2.4, Req-10.4.2.b, 1487, 169

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-w /etc/localtime -p wa -k audit_time_rules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/localtime -p wa -k audit_time_rules
The -k option allows for the specification of a key in string form that can be used for better reporting capability through ausearch and aureport and should always be used.

Rationale

Arbitrary changes to the system time can be used to obfuscate nefarious activities in log files, as well as to confuse network services that are highly dependent upon an accurate system time (such as sshd). All changes to the system time should be audited.

Record Events that Modify the System's Discretionary Access Controls - chmodxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chmod low

Record Events that Modify the System's Discretionary Access Controls - chmod

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chmod
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chmod  -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S chmod -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chmod  -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - chownxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chown low

Record Events that Modify the System's Discretionary Access Controls - chown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_chown
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S chown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S chown -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - fchmodxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmod low

Record Events that Modify the System's Discretionary Access Controls - fchmod

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmod
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchmod -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmod -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - fchmodatxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmodat low

Record Events that Modify the System's Discretionary Access Controls - fchmodat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchmodat
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchmodat -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchmodat -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - fchownxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchown low

Record Events that Modify the System's Discretionary Access Controls - fchown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchown
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchown -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - fchownatxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchownat low

Record Events that Modify the System's Discretionary Access Controls - fchownat

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fchownat
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fchownat -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fchownat -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - fremovexattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fremovexattr low

Record Events that Modify the System's Discretionary Access Controls - fremovexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fremovexattr
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - fsetxattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fsetxattr low

Record Events that Modify the System's Discretionary Access Controls - fsetxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_fsetxattr
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S fsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S fsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - lchownxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lchown low

Record Events that Modify the System's Discretionary Access Controls - lchown

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lchown
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lchown -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lchown -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - lremovexattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lremovexattr low

Record Events that Modify the System's Discretionary Access Controls - lremovexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lremovexattr
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lremovexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - lsetxattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lsetxattr low

Record Events that Modify the System's Discretionary Access Controls - lsetxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_lsetxattr
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S lsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S lsetxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - removexattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_removexattr low

Record Events that Modify the System's Discretionary Access Controls - removexattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_removexattr
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S removexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S removexattr -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify the System's Discretionary Access Controls - setxattrxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_setxattr low

Record Events that Modify the System's Discretionary Access Controls - setxattr

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_dac_modification_setxattr
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.5.5, 5.2.10

Description

At a minimum the audit system should collect file permission changes for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S setxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod
If the system is 64 bit then also add the following line:
-a always,exit -F arch=b64 -S setxattr -F auid>=1000 -F auid!=4294967295 -k perm_mod

Rationale

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing DAC modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Warnings
warning  Note that these rules can be configured in a number of ways while still achieving the desired effect. Here the system calls have been placed independent of other system calls. Grouping these system calls with others as identifying earlier in this guide is more efficient.
Record Events that Modify User/Group Informationxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification low

Record Events that Modify User/Group Information

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_usergroup_modification
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-2(4), AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 18, 172, 1403, 2130, RHEL-07-030710, Req-10.2.5, 5.2.5, SRG–OS–000004–GPOS–00004, SRG–OS–000239–GPOS–00089, SRG–OS–000241–GPOS–00090, SRG–OS–000241–GPOS–00091, SRG–OS–000303–GPOS–00120, SRG–OS–000476–GPOS–00221

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, in order to capture events that modify account changes:

-w /etc/group -p wa -k audit_rules_usergroup_modification
-w /etc/passwd -p wa -k audit_rules_usergroup_modification
-w /etc/gshadow -p wa -k audit_rules_usergroup_modification
-w /etc/shadow -p wa -k audit_rules_usergroup_modification
-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification

If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, in order to capture events that modify account changes:
-w /etc/group -p wa -k audit_rules_usergroup_modification
-w /etc/passwd -p wa -k audit_rules_usergroup_modification
-w /etc/gshadow -p wa -k audit_rules_usergroup_modification
-w /etc/shadow -p wa -k audit_rules_usergroup_modification
-w /etc/security/opasswd -p wa -k audit_rules_usergroup_modification

Rationale

In addition to auditing new user and group accounts, these watches will alert the system administrator(s) to any modifications. Any unexpected users, groups, or modifications should be investigated for legitimacy.

Record Events that Modify the System's Network Environmentxccdf_org.ssgproject.content_rule_audit_rules_networkconfig_modification low

Record Events that Modify the System's Network Environment

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_networkconfig_modification
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, Req-10.5.5, 5.2.6

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:

-a always,exit -F arch=ARCH -S sethostname -S setdomainname -k audit_rules_networkconfig_modification
-w /etc/issue -p wa -k audit_rules_networkconfig_modification
-w /etc/issue.net -p wa -k audit_rules_networkconfig_modification
-w /etc/hosts -p wa -k audit_rules_networkconfig_modification
-w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S sethostname -S setdomainname -k audit_rules_networkconfig_modification
-w /etc/issue -p wa -k audit_rules_networkconfig_modification
-w /etc/issue.net -p wa -k audit_rules_networkconfig_modification
-w /etc/hosts -p wa -k audit_rules_networkconfig_modification
-w /etc/sysconfig/network -p wa -k audit_rules_networkconfig_modification

Rationale

The network environment should not be modified by anything other than administrator action. Any change to network parameters should be audited.

System Audit Logs Must Have Mode 0640 or Less Permissivexccdf_org.ssgproject.content_rule_file_permissions_var_log_audit medium

System Audit Logs Must Have Mode 0640 or Less Permissive

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_var_log_audit
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, AU-1(b), AU-9, IR-5, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Req-10.5, Test attestation on 20121024 by DS

Description

If log_group in /etc/audit/auditd.conf is set to a group other than the root group account, change the mode of the audit log files with the following command:

$ sudo chmod 0640 audit_file

Otherwise, change the mode of the audit log files with the following command:
$ sudo chmod 0600 audit_file

Rationale

If users can write to audit logs, audit trails can be modified or destroyed.

System Audit Logs Must Be Owned By Rootxccdf_org.ssgproject.content_rule_file_ownership_var_log_audit medium

System Audit Logs Must Be Owned By Root

Rule IDxccdf_org.ssgproject.content_rule_file_ownership_var_log_audit
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, AU-1(b), AU-9, IR-5, 163, SRG-OS-000058-GPOS-00028, RHEL-07-030120, Req-10.5.1, Test attestation on 20121024 by DS

Description

To properly set the owner of /var/log, run the command:

$ sudo chown root /var/log

Rationale

Unauthorized disclosure of audit records can reveal system and configuration data to attackers, thus compromising its confidentiality.

Record Events that Modify the System's Mandatory Access Controlsxccdf_org.ssgproject.content_rule_audit_rules_mac_modification low

Record Events that Modify the System's Mandatory Access Controls

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_mac_modification
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, Req-10.5.5, 5.2.7

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-w /etc/selinux/ -p wa -k MAC-policy
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/selinux/ -p wa -k MAC-policy

Rationale

The system's mandatory access policy (SELinux) should not be arbitrarily changed by anything other than administrator action. All changes to MAC policy should be audited.

Record Attempts to Alter Process and Session Initiation Informationxccdf_org.ssgproject.content_rule_audit_rules_session_events low

Record Attempts to Alter Process and Session Initiation Information

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_session_events
Result
pass
Time2016-07-11T14:22:09
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, Req-10.2.3, 5.2.9

Description

The audit system already collects process information for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d in order to watch for attempted manual edits of files involved in storing such process information:

-w /var/run/utmp -p wa -k session
-w /var/log/btmp -p wa -k session
-w /var/log/wtmp -p wa -k session
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file in order to watch for attempted manual edits of files involved in storing such process information:
-w /var/run/utmp -p wa -k session
-w /var/log/btmp -p wa -k session
-w /var/log/wtmp -p wa -k session

Rationale

Manual editing of these files may indicate nefarious activity, such as an attacker attempting to remove evidence of an intrusion.

Ensure auditd Collects Unauthorized Access Attempts to Files (unsuccessful)xccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification medium

Ensure auditd Collects Unauthorized Access Attempts to Files (unsuccessful)

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_unsuccessful_file_modification
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 172, 2884, SRG-OS-000064-GPOS-00033, SRG-OS-000458-GPOS-00203, SRG-OS-000461-GPOS-00205, SRG-OS-000392-GPOS-00172, RHEL-07-030420, Req-10.2.4, Req-10.2.1, 5.2.10

Description

At a minimum the audit system should collect unauthorized file accesses for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d:

-a always,exit -F arch=b32 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=4294967295 -k access
-a always,exit -F arch=b32 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=4294967295 -k access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=4294967295 -k access
-a always,exit -F arch=b64 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=4294967295 -k access
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file:
-a always,exit -F arch=b32 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=4294967295 -k access
-a always,exit -F arch=b32 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=4294967295 -k access
If the system is 64 bit then also add the following lines:
-a always,exit -F arch=b64 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EACCES -F auid>=1000 -F auid!=4294967295 -k access
-a always,exit -F arch=b64 -S creat -S open -S openat -S open_by_handle_at -S truncate -S ftruncate -F exit=-EPERM -F auid>=1000 -F auid!=4294967295 -k access

Rationale

Unsuccessful attempts to access files could be an indicator of malicious activity on a system. Auditing these events could serve as evidence of potential system compromise.

Ensure auditd Collects Information on the Use of Privileged Commandsxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands medium

Ensure auditd Collects Information on the Use of Privileged Commands

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_privileged_commands
Result
pass
Time2016-07-11T14:22:40
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-2(4), AU-6(9), AU-12(a), AU-12(c), IR-5, 2234, SRG-OS-000327-GPOS-00127, RHEL-07-030310, Req-10.2.2, 5.2.10, Test attestation on 20121024 by DS

Description

At a minimum the audit system should collect the execution of privileged commands for all users and root. To find the relevant setuid / setgid programs, run the following command for each local partition PART:

$ sudo find PART -xdev -type f -perm -4000 -o -type f -perm -2000 2>/dev/null
If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add a line of the following form to a file with suffix .rules in the directory /etc/audit/rules.d for each setuid / setgid program on the system, replacing the SETUID_PROG_PATH part with the full path of that setuid / setgid program in the list:
-a always,exit -F path=SETUID_PROG_PATH -F perm=x -F auid>=1000 -F auid!=4294967295 -k privileged
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add a line of the following form to /etc/audit/audit.rules for each setuid / setgid program on the system, replacing the SETUID_PROG_PATH part with the full path of that setuid / setgid program in the list:
-a always,exit -F path=SETUID_PROG_PATH -F perm=x -F auid>=1000 -F auid!=4294967295 -k privileged

Rationale

Misuse of privileged functions, either intentionally or unintentionally by authorized users, or by unauthorized external entities that have compromised system accounts, is a serious and ongoing concern and can have significant adverse impacts on organizations. Auditing the use of privileged functions is one way to detect such misuse and identify the risk from insider and advanced persistent threast.
Privileged programs are subject to escalation-of-privilege attacks, which attempt to subvert their normal role of providing some necessary but limited capability. As such, motivation exists to monitor these programs for unusual activity.

Ensure auditd Collects Information on Exporting to Media (successful)xccdf_org.ssgproject.content_rule_audit_rules_media_export medium

Ensure auditd Collects Information on Exporting to Media (successful)

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_media_export
Result
pass
Time2016-07-11T14:22:40
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-3(1), AU-12(a), AU-12(c), IR-5, 135, 2884, SRG-OS-000042-GPOS-00020, SRG-OS-000392-GPOS-00172, RHEL-07-030530, Req-10.2.7, 5.2.13, Test attestation on 20121024 by DS

Description

At a minimum the audit system should collect media exportation events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:

-a always,exit -F arch=ARCH -S mount -F auid>=1000 -F auid!=4294967295 -k export
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S mount -F auid>=1000 -F auid!=4294967295 -k export

Rationale

The unauthorized exportation of data to external media could result in an information leak where classified information, Privacy Act information, and intellectual property could be lost. An audit trail should be created each time a filesystem is mounted to help identify and guard against information loss.

Ensure auditd Collects File Deletion Events by Userxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events medium

Ensure auditd Collects File Deletion Events by User

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_file_deletion_events
Result
pass
Time2016-07-11T14:22:40
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 366, SRG-OS-000480-GPOS-00227, RHEL-07-030750, Req-10.2.7, 5.2.14

Description

At a minimum the audit system should collect file deletion events for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d, setting ARCH to either b32 or b64 as appropriate for your system:

-a always,exit -F arch=ARCH -S rmdir -S unlink -S unlinkat -S rename -S renameat -F auid>=1000 -F auid!=4294967295 -k delete
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file, setting ARCH to either b32 or b64 as appropriate for your system:
-a always,exit -F arch=ARCH -S rmdir -S unlink -S unlinkat -S rename -S renameat -F auid>=1000 -F auid!=4294967295 -k delete

Rationale

Auditing file deletions will create an audit trail for files that are removed from the system. The audit trail could aid in system troubleshooting, as well as, detecting malicious processes that attempt to delete log files to conceal their presence.

Ensure auditd Collects System Administrator Actionsxccdf_org.ssgproject.content_rule_audit_rules_sysadmin_actions low

Ensure auditd Collects System Administrator Actions

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_sysadmin_actions
Result
pass
Time2016-07-11T14:22:40
Severitylow
Identifiers and References

identifiers: 

references:  AC-2(7)(b), AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 126, Req-10.2.2, Req-10.2.5.b, Test attestation on 20121024 by DS

Description

At a minimum the audit system should collect administrator actions for all users and root. If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d:

-w /etc/sudoers -p wa -k actions
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file:
-w /etc/sudoers -p wa -k actions

Rationale

The actions taken by system administrators should be audited to keep a record of what was executed on the system, as well as, for accountability purposes.

Ensure auditd Collects Information on Kernel Module Loading and Unloadingxccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading medium

Ensure auditd Collects Information on Kernel Module Loading and Unloading

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_kernel_module_loading
Result
pass
Time2016-07-11T14:22:40
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(7), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-12(a), AU-12(c), IR-5, 172, SRG-OS-000471-GPOS-00216, SRG-OS-000477, GPOS-00222, RHEL-07-030670, Req-10.2.7, 5.2.17

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following lines to a file with suffix .rules in the directory /etc/audit/rules.d to capture kernel module loading and unloading events, setting ARCH to either b32 or b64 as appropriate for your system:

-w /usr/sbin/insmod -p x -k modules
-w /usr/sbin/rmmod -p x -k modules
-w /usr/sbin/modprobe -p x -k modules
-a always,exit -F arch=ARCH -S init_module -S delete_module -k modules
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following lines to /etc/audit/audit.rules file in order to capture kernel module loading and unloading events, setting ARCH to either b32 or b64 as appropriate for your system:
-w /usr/sbin/insmod -p x -k modules
-w /usr/sbin/rmmod -p x -k modules
-w /usr/sbin/modprobe -p x -k modules
-a always,exit -F arch=ARCH -S init_module -S delete_module -k modules

Rationale

The addition/removal of kernel modules can be used to alter the behavior of the kernel and potentially introduce malicious code into kernel space. It is important to have an audit trail of modules that have been introduced into the kernel.

Make the auditd Configuration Immutablexccdf_org.ssgproject.content_rule_audit_rules_immutable low

Make the auditd Configuration Immutable

Rule IDxccdf_org.ssgproject.content_rule_audit_rules_immutable
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  AC-6, AU-1(b), AU-2(a), AU-2(c), AU-2(d), IR-5, Req-10.5.2, 5.2.18

Description

If the auditd daemon is configured to use the augenrules program to read audit rules during daemon startup (the default), add the following line to a file with suffix .rules in the directory /etc/audit/rules.d in order to make the auditd configuration immutable:

-e 2
If the auditd daemon is configured to use the auditctl utility to read audit rules during daemon startup, add the following line to /etc/audit/audit.rules file in order to make the auditd configuration immutable:
-e 2
With this setting, a reboot will be required to change any audit rules.

Rationale

Making the audit configuration immutable prevents accidental as well as malicious modification of the audit rules, although it may be problematic if legitimate changes are needed during system operation

Enable auditd Servicexccdf_org.ssgproject.content_rule_service_auditd_enabled medium

Enable auditd Service

Rule IDxccdf_org.ssgproject.content_rule_service_auditd_enabled
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AU-3, AC-17(1), AU-1(b), AU-10, AU-12(a), AU-12(c), AU-14(1), IR-5, 126, 131, SRG-OS-000038-GPOS-00016, SRG-OS-000039-GPOS-00017, SRG-OS-000042-GPOS-00021, SRG-OS-000254-GPOS-00095, SRG-OS-000255-GPOS-00096, RHEL-07-030010, Req-10, 5.2.2, Test attestation on 20121024 by DS

Description

The auditd service is an essential userspace component of the Linux Auditing System, as it is responsible for writing audit records to disk. The auditd service can be enabled with the following command:

$ sudo systemctl enable auditd.service

Rationale

Without establishing what type of events occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack.
Ensuring the auditd service is active ensures audit records generated by the kernel are appropriately recorded.

Enable Auditing for Processes Which Start Prior to the Audit Daemonxccdf_org.ssgproject.content_rule_bootloader_audit_argument medium

Enable Auditing for Processes Which Start Prior to the Audit Daemon

Rule IDxccdf_org.ssgproject.content_rule_bootloader_audit_argument
Result
pass
Time2016-07-11T14:22:09
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(1), AU-14(1), AU-1(b), AU-2(a), AU-2(c), AU-2(d), AU-10, IR-5, 1464, 130, Req-10.3, 5.2.3

Description

To ensure all processes can be audited, even those which start prior to the audit daemon, add the argument audit=1 to the default GRUB 2 command line for the Linux operating system in /etc/default/grub, in the manner below:

GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=VolGroup/LogVol06 rd.lvm.lv=VolGroup/lv_swap rhgb quiet rd.shell=0 audit=1"

Rationale

Each process on the system carries an "auditable" flag which indicates whether its activities can be audited. Although auditd takes care of enabling this for all processes which launch after it does, adding the kernel argument ensures it is set for every process during boot.

Warnings
warning  The GRUB 2 configuration file, grub.cfg, is automatically updated each time a new kernel is installed. Note that any changes to /etc/default/grub require rebuilding the grub.cfg file. To update the GRUB 2 configuration file manually, use the
grub2-mkconfig -o
command as follows:
  • On BIOS-based machines, issue the following command as root:
    ~]# grub2-mkconfig -o /boot/grub2/grub.cfg
  • On UEFI-based machines, issue the following command as root:
    ~]# grub2-mkconfig -o /boot/efi/EFI/redhat/grub.cfg
Disable xinetd Servicexccdf_org.ssgproject.content_rule_service_xinetd_disabled medium

Disable xinetd Service

Rule IDxccdf_org.ssgproject.content_rule_service_xinetd_disabled
Result
pass
Time2016-07-11T14:22:41
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 305, Test attestation on 20121026 by DS

Description

The xinetd service can be disabled with the following command:

$ sudo systemctl disable xinetd.service

Rationale

The xinetd service provides a dedicated listener service for some programs, which is no longer necessary for commonly-used network services. Disabling it ensures that these uncommon services are not running, and also prevents attacks against xinetd itself.

Uninstall xinetd Packagexccdf_org.ssgproject.content_rule_package_xinetd_removed low

Uninstall xinetd Package

Rule IDxccdf_org.ssgproject.content_rule_package_xinetd_removed
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 305, 2.1.11, Test attestation on 20121026 by DS

Description

The xinetd package can be uninstalled with the following command:

$ sudo yum erase xinetd

Rationale

Removing the xinetd package decreases the risk of the xinetd service's accidental (or intentional) activation.

Install tcp_wrappers Packagexccdf_org.ssgproject.content_rule_package_tcp_wrappers_installed medium

Install tcp_wrappers Package

Rule IDxccdf_org.ssgproject.content_rule_package_tcp_wrappers_installed
Result
notselected
Time2016-07-11T14:22:41
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

When network services are using the xinetd service, the tcp_wrappers package should be installed. The tcp_wrappers package can be installed with the following command:

$ sudo yum install tcp_wrappers

Rationale

Access control methods provide the ability to enhance system security posture by restricting services and known good IP addresses and address ranges. This prevents connections from unknown hosts and protocols.

Disable telnet Servicexccdf_org.ssgproject.content_rule_service_telnet_disabled high

Disable telnet Service

Rule IDxccdf_org.ssgproject.content_rule_service_telnet_disabled
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, IA-5(1)(c), http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20140922 by JL

Description

The telnet service configuration file /etc/xinetd.d/telnet is not created automatically. If it was created manually, check the /etc/xinetd.d/telnet file and ensure that disable = no is changed to read disable = yes as follows below:

# description: The telnet server serves telnet sessions; it uses \\
#       unencrypted username/password pairs for authentication.
service telnet
{
        flags           = REUSE
        socket_type     = stream

        wait            = no
        user            = root
        server          = /usr/sbin/in.telnetd
        log_on_failure  += USERID
        disable         = yes
}
If the /etc/xinetd.d/telnet file does not exist, make sure that the activation of the telnet service on system boot is disabled via the following command: The rexec socket can be disabled with the following command:
$ sudo systemctl disable rexec.socket

Rationale

The telnet protocol uses unencrypted network communication, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network. The telnet protocol is also subject to man-in-the-middle attacks.

Uninstall telnet-server Packagexccdf_org.ssgproject.content_rule_package_telnet-server_removed high

Uninstall telnet-server Package

Rule IDxccdf_org.ssgproject.content_rule_package_telnet-server_removed
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7(a), 381, SRG-OS-000095-GPOS-00049, RHEL-07-021910, 2.1.1, Test attestation on 20121026 by DS

Description

The telnet-server package can be uninstalled with the following command:

$ sudo yum erase telnet-server

Rationale

It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities are often overlooked and therefore may remain unsecure. They increase the risk to the platform by providing additional attack vectors.
The telnet service provides an unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session. If a privileged user were to login using this service, the privileged user password could be compromised.
Removing the telnet-server package decreases the risk of the telnet service's accidental (or intentional) activation.

Remove telnet Clientsxccdf_org.ssgproject.content_rule_package_telnet_removed low

Remove telnet Clients

Rule IDxccdf_org.ssgproject.content_rule_package_telnet_removed
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  2.1.2

Description

The telnet client allows users to start connections to other systems via the telnet protocol.

Rationale

The telnet protocol is insecure and unencrypted. The use of an unencrypted transmission medium could allow an unauthorized user to steal credentials. The ssh package provides an encrypted session and stronger security and is included in Red Hat Enterprise Linux.

Uninstall rsh-server Packagexccdf_org.ssgproject.content_rule_package_rsh-server_removed high

Uninstall rsh-server Package

Rule IDxccdf_org.ssgproject.content_rule_package_rsh-server_removed
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7(a), 381, SRG-OS-000095-GPOS-00049, RHEL-07-020000, 2.1.3, Test attestation on 20121026 by DS

Description

The rsh-server package can be uninstalled with the following command:

$ sudo yum erase rsh-server

Rationale

The rsh-server service provides unencrypted remote access service which does not provide for the confidentiality and integrity of user passwords or the remote session and has very weak authentication. If a privileged user were to login using this service, the privileged user password could be compromised. The rsh-server package provides several obsolete and insecure network services. Removing it decreases the risk of those services' accidental (or intentional) activation.

Disable rexec Servicexccdf_org.ssgproject.content_rule_service_rexec_disabled high

Disable rexec Service

Rule IDxccdf_org.ssgproject.content_rule_service_rexec_disabled
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 68, 1436, Test attestation on 20121026 by DS

Description

The rexec service, which is available with the rsh-server package and runs as a service through xinetd or separately as a systemd socket, should be disabled. If using xinetd, set disable to yes in /etc/xinetd.d/rexec. If using systemd, The rexec socket can be disabled with the following command:

$ sudo systemctl disable rexec.socket

Rationale

The rexec service uses unencrypted network communications, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network.

Disable rsh Servicexccdf_org.ssgproject.content_rule_service_rsh_disabled high

Disable rsh Service

Rule IDxccdf_org.ssgproject.content_rule_service_rsh_disabled
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, IA-5(1)(c), 68, 1436, Test attestation on 20121026 by DS

Description

The rsh service, which is available with the rsh-server package and runs as a service through xinetd or separately as a systemd socket, should be disabled. If using xinetd, set disable to yes in /etc/xinetd.d/rsh. If using systemd, The rsh socket can be disabled with the following command:

$ sudo systemctl disable rsh.socket

Rationale

The rsh service uses unencrypted network communications, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network.

Uninstall rsh Packagexccdf_org.ssgproject.content_rule_package_rsh_removed low

Uninstall rsh Package

Rule IDxccdf_org.ssgproject.content_rule_package_rsh_removed
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  2.1.4, Test attestation on 20140530 by JL

Description

The rsh package contains the client commands for the rsh services

Rationale

These legacy clients contain numerous security exposures and have been replaced with the more secure SSH package. Even if the server is removed, it is best to ensure the clients are also removed to prevent users from inadvertently attempting to use these commands and therefore exposing their credentials. Note that removing the rsh package removes the clients for rsh,rcp, and rlogin.

Disable rlogin Servicexccdf_org.ssgproject.content_rule_service_rlogin_disabled high

Disable rlogin Service

Rule IDxccdf_org.ssgproject.content_rule_service_rlogin_disabled
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, IA-5(1)(c), 1436, Test attestation on 20121026 by DS

Description

The rlogin service, which is available with the rsh-server package and runs as a service through xinetd or separately as a systemd socket, should be disabled. If using xinetd, set disable to yes in /etc/xinetd.d/rlogin. If using systemd, The rlogin socket can be disabled with the following command:

$ sudo systemctl disable rlogin.socket

Rationale

The rlogin service uses unencrypted network communications, which means that data from the login session, including passwords and all other information transmitted during the session, can be stolen by eavesdroppers on the network.

Remove Rsh Trust Filesxccdf_org.ssgproject.content_rule_no_rsh_trust_files high

Remove Rsh Trust Files

Rule IDxccdf_org.ssgproject.content_rule_no_rsh_trust_files
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 1436, Test attestation on 20121026 by DS

Description

The files /etc/hosts.equiv and ~/.rhosts (in each user's home directory) list remote hosts and users that are trusted by the local system when using the rshd daemon. To remove these files, run the following command to delete them from any location:

$ sudo rm /etc/hosts.equiv
$ rm ~/.rhosts

Rationale

Trust files are convenient, but when used in conjunction with the R-services, they can allow unauthenticated access to a system.

Uninstall ypserv Packagexccdf_org.ssgproject.content_rule_package_ypserv_removed high

Uninstall ypserv Package

Rule IDxccdf_org.ssgproject.content_rule_package_ypserv_removed
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7(a), 381, SRG-OS-000095-GPOS-00049, RHEL-07-020010, 2.1.6, Test attestation on 20121026 by DS

Description

The ypserv package can be uninstalled with the following command:

$ sudo yum erase ypserv

Rationale

The NIS service provides an unencrypted authentication service which does not provide for the confidentiality and integrity of user passwords or the remote session. Removing the ypserv package decreases the risk of the accidental (or intentional) activation of NIS or NIS+ services.

Disable ypbind Servicexccdf_org.ssgproject.content_rule_service_ypbind_disabled medium

Disable ypbind Service

Rule IDxccdf_org.ssgproject.content_rule_service_ypbind_disabled
Result
pass
Time2016-07-11T14:22:41
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 305, Test attestation on 20121026 by DS

Description

The ypbind service, which allows the system to act as a client in a NIS or NIS+ domain, should be disabled. The ypbind service can be disabled with the following command:

$ sudo systemctl disable ypbind.service

Rationale

Disabling the ypbind service ensures the system is not acting as a client in a NIS or NIS+ domain.

Remove NIS Clientxccdf_org.ssgproject.content_rule_package_ypbind_removed low

Remove NIS Client

Rule IDxccdf_org.ssgproject.content_rule_package_ypbind_removed
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  2.1.5

Description

The Network Information Service (NIS), formerly known as Yellow Pages, is a client-server directory service protocol used to distribute system configuration files. The NIS client (ypbind) was used to bind a machine to an NIS server and receive the distributed configuration files.

Rationale

The NIS service is inherently an insecure system that has been vulnerable to DOS attacks, buffer overflows and has poor authentication for querying NIS maps. NIS generally has been replaced by such protocols as Lightweight Directory Access Protocol (LDAP). It is recommended that the service be removed.

Disable tftp Servicexccdf_org.ssgproject.content_rule_service_tftp_disabled medium

Disable tftp Service

Rule IDxccdf_org.ssgproject.content_rule_service_tftp_disabled
Result
pass
Time2016-07-11T14:22:41
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 1436, Test attestation on 20121026 by DS

Description

The tftp service should be disabled. The tftp service can be disabled with the following command:

$ sudo systemctl disable tftp.service

Rationale

Disabling the tftp service ensures the system is not acting as a TFTP server, which does not provide encryption or authentication.

Uninstall tftp-server Packagexccdf_org.ssgproject.content_rule_package_tftp-server_removed high

Uninstall tftp-server Package

Rule IDxccdf_org.ssgproject.content_rule_package_tftp-server_removed
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-6(c), CM-7, 318, 368, 1812, 1813, 1814, SRG-OS-000480-GPOS-00227, RHEL-07-040500, 2.1.8, Test attestation on 20121026 by DS

Description

The tftp-server package can be removed with the following command:

$ sudo yum erase tftp-server

Rationale

Removing the tftp-server package decreases the risk of the accidental (or intentional) activation of tftp services. If TFTP is required for operational support (such as transmission of router configurations), its use must be documented with the Information Systems Securty Manager (ISSM), restricted to only authorized personnel, and have access control rules established.

Remove tftp Daemonxccdf_org.ssgproject.content_rule_package_tftp_removed high

Remove tftp Daemon

Rule IDxccdf_org.ssgproject.content_rule_package_tftp_removed
Result
pass
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  2.1.7

Description

Trivial File Transfer Protocol (TFTP) is a simple file transfer protocol, typically used to automatically transfer configuration or boot files between machines. TFTP does not support authentication and can be easily hacked. The package tftp is a client program that allows for connections to a tftp server.

Rationale

It is recommended that TFTP be removed, unless there is a specific need for TFTP (such as a boot server). In that case, use extreme caution when configuring the services.

Ensure tftp Daemon Uses Secure Modexccdf_org.ssgproject.content_rule_tftpd_uses_secure_mode high

Ensure tftp Daemon Uses Secure Mode

Rule IDxccdf_org.ssgproject.content_rule_tftpd_uses_secure_mode
Result
notselected
Time2016-07-11T14:22:41
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 366

Description

If running the tftp service is necessary, it should be configured to change its root directory at startup. To do so, ensure /etc/xinetd.d/tftp includes -s as a command line argument, as shown in the following example (which is also the default):

server_args = -s /var/lib/tftpboot

Rationale

Using the -s option causes the TFTP service to only serve files from the given directory. Serving files from an intentionally-specified directory reduces the risk of sharing files which should remain private.

Uninstall talk-server Packagexccdf_org.ssgproject.content_rule_package_talk-server_removed medium

Uninstall talk-server Package

Rule IDxccdf_org.ssgproject.content_rule_package_talk-server_removed
Result
pass
Time2016-07-11T14:22:41
Severitymedium
Identifiers and References

identifiers: 

references:  2.1.10, Test attestation on 20140625 by JL

Description

The talk-server package can be removed with the following command:

$ sudo yum erase talk-server

Rationale

The talk software presents a security risk as it uses unencrypted protocols for communications. Removing the talk-server package decreases the risk of the accidental (or intentional) activation of talk services.

Uninstall talk Packagexccdf_org.ssgproject.content_rule_package_talk_removed low

Uninstall talk Package

Rule IDxccdf_org.ssgproject.content_rule_package_talk_removed
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  2.1.9, Test attestation on 20140625 by JL

Description

The talk package contains the client program for the Internet talk protocol, which allows the user to chat with other users on different systems. Talk is a communication program which copies lines from one terminal to the terminal of another user. The talk package can be removed with the following command:

$ sudo yum erase talk

Rationale

The talk software presents a security risk as it uses unencrypted protocols for communications. Removing the talk package decreases the risk of the accidental (or intentional) activation of talk client program.

Disable Automatic Bug Reporting Tool (abrtd)xccdf_org.ssgproject.content_rule_service_abrtd_disabled low

Disable Automatic Bug Reporting Tool (abrtd)

Rule IDxccdf_org.ssgproject.content_rule_service_abrtd_disabled
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, http://iase.disa.mil/stigs/cci/Pages/index.aspx, Test attestation on 20140921 by JL

Description

The Automatic Bug Reporting Tool (abrtd) daemon collects and reports crash data when an application crash is detected. Using a variety of plugins, abrtd can email crash reports to system administrators, log crash reports to files, or forward crash reports to a centralized issue tracking system such as RHTSupport. The abrtd service can be disabled with the following command:

$ sudo systemctl disable abrtd.service

Rationale

Mishandling crash data could expose sensitive information about vulnerabilities in software executing on the local machine, as well as sensitive information from within a process's address space or registers.

Disable Advanced Configuration and Power Interface (acpid)xccdf_org.ssgproject.content_rule_service_acpid_disabled low

Disable Advanced Configuration and Power Interface (acpid)

Rule IDxccdf_org.ssgproject.content_rule_service_acpid_disabled
Result
pass
Time2016-07-11T14:22:41
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The Advanced Configuration and Power Interface Daemon (acpid) dispatches ACPI events (such as power/reset button depressed) to userspace programs. The acpid service can be disabled with the following command:

$ sudo systemctl disable acpid.service

Rationale

ACPI support is highly desirable for systems in some network roles, such as laptops or desktops. For other systems, such as servers, it may permit accidental or trivially achievable denial of service situations and disabling it is appropriate.

Disable Certmonger Service (certmonger)xccdf_org.ssgproject.content_rule_service_certmonger_disabled low

Disable Certmonger Service (certmonger)

Rule IDxccdf_org.ssgproject.content_rule_service_certmonger_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Certmonger is a D-Bus based service that attempts to simplify interaction with certifying authorities on networks which use public-key infrastructure. It is often combined with Red Hat's IPA (Identity Policy Audit) security information management solution to aid in the management of certificates. The certmonger service can be disabled with the following command:

$ sudo systemctl disable certmonger.service

Rationale

The services provided by certmonger may be essential for systems fulfilling some roles a PKI infrastructure, but its functionality is not necessary for many other use cases.

Disable Control Group Config (cgconfig)xccdf_org.ssgproject.content_rule_service_cgconfig_disabled low

Disable Control Group Config (cgconfig)

Rule IDxccdf_org.ssgproject.content_rule_service_cgconfig_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Control groups allow an administrator to allocate system resources (such as CPU, memory, network bandwidth, etc) among a defined group (or groups) of processes executing on a system. The cgconfig daemon starts at boot and establishes the predefined control groups. The cgconfig service can be disabled with the following command:

$ sudo systemctl disable cgconfig.service

Rationale

Unless control groups are used to manage system resources, running the cgconfig service is not necessary.

Disable Control Group Rules Engine (cgred)xccdf_org.ssgproject.content_rule_service_cgred_disabled low

Disable Control Group Rules Engine (cgred)

Rule IDxccdf_org.ssgproject.content_rule_service_cgred_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The cgred service moves tasks into control groups according to parameters set in the /etc/cgrules.conf configuration file. The cgred service can be disabled with the following command:

$ sudo systemctl disable cgred.service

Rationale

Unless control groups are used to manage system resources, running the cgred service service is not necessary.

Disable CPU Speed (cpupower)xccdf_org.ssgproject.content_rule_service_cpupower_disabled low

Disable CPU Speed (cpupower)

Rule IDxccdf_org.ssgproject.content_rule_service_cpupower_disabled
Result
notselected
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The cpupower service can adjust the clock speed of supported CPUs based upon the current processing load thereby conserving power and reducing heat. The cpupower service can be disabled with the following command:

$ sudo systemctl disable cpupower.service

Rationale

The cpupower service is only necessary if adjusting the CPU clock speed provides benefit. Traditionally this has included laptops (to enhance battery life), but may also apply to server or desktop environments where conserving power is highly desirable or necessary.

Enable IRQ Balance (irqbalance)xccdf_org.ssgproject.content_rule_service_irqbalance_enabled low

Enable IRQ Balance (irqbalance)

Rule IDxccdf_org.ssgproject.content_rule_service_irqbalance_enabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The irqbalance service optimizes the balance between power savings and performance through distribution of hardware interrupts across multiple processors. The irqbalance service can be enabled with the following command:

$ sudo systemctl enable irqbalance.service

Rationale

In an environment with multiple processors (now common), the irqbalance service provides potential speedups for handling interrupt requests.

Disable KDump Kernel Crash Analyzer (kdump)xccdf_org.ssgproject.content_rule_service_kdump_disabled medium

Disable KDump Kernel Crash Analyzer (kdump)

Rule IDxccdf_org.ssgproject.content_rule_service_kdump_disabled
Result
pass
Time2016-07-11T14:22:42
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, CM-6(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-021230

Description

The kdump service provides a kernel crash dump analyzer. It uses the kexec system call to boot a secondary kernel ("capture" kernel) following a system crash, which can load information from the crashed kernel for analysis. The kdump service can be disabled with the following command:

$ sudo systemctl disable kdump.service

Rationale

Kernel core dumps may contain the full contents of system memory at the time of the crash. Kernel core dumps consume a considerable amount of disk space and may result in denial of service by exhausting the available space on the target file system partition. Unless the system is used for kernel development or testing, there is little need to run the kdump service.

Disable Software RAID Monitor (mdmonitor)xccdf_org.ssgproject.content_rule_service_mdmonitor_disabled low

Disable Software RAID Monitor (mdmonitor)

Rule IDxccdf_org.ssgproject.content_rule_service_mdmonitor_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The mdmonitor service is used for monitoring a software RAID array; hardware RAID setups do not use this service. The mdmonitor service can be disabled with the following command:

$ sudo systemctl disable mdmonitor.service

Rationale

If software RAID monitoring is not required, there is no need to run this service.

Disable D-Bus IPC Service (messagebus)xccdf_org.ssgproject.content_rule_service_messagebus_disabled low

Disable D-Bus IPC Service (messagebus)

Rule IDxccdf_org.ssgproject.content_rule_service_messagebus_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

D-Bus provides an IPC mechanism used by a growing list of programs, such as those used for Gnome, Bluetooth, and Avahi. Due to these dependencies, disabling D-Bus may not be practical for many systems. The messagebus service can be disabled with the following command:

$ sudo systemctl disable messagebus.service

Rationale

If no services which require D-Bus are needed, then it can be disabled. As a broker for IPC between processes of different privilege levels, it could be a target for attack. However, disabling D-Bus is likely to be impractical for any system which needs to provide a graphical login session.

Disable Network Console (netconsole)xccdf_org.ssgproject.content_rule_service_netconsole_disabled low

Disable Network Console (netconsole)

Rule IDxccdf_org.ssgproject.content_rule_service_netconsole_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 381

Description

The netconsole service is responsible for loading the netconsole kernel module, which logs kernel printk messages over UDP to a syslog server. This allows debugging of problems where disk logging fails and serial consoles are impractical. The netconsole service can be disabled with the following command:

$ sudo systemctl disable netconsole.service

Rationale

The netconsole service is not necessary unless there is a need to debug kernel panics, which is not common.

Disable ntpdate Service (ntpdate)xccdf_org.ssgproject.content_rule_service_ntpdate_disabled low

Disable ntpdate Service (ntpdate)

Rule IDxccdf_org.ssgproject.content_rule_service_ntpdate_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 382, Test attestation on 20121024 by DS

Description

The ntpdate service sets the local hardware clock by polling NTP servers when the system boots. It synchronizes to the NTP servers listed in /etc/ntp/step-tickers or /etc/ntp.conf and then sets the local hardware clock to the newly synchronized system time. The ntpdate service can be disabled with the following command:

$ sudo systemctl disable ntpdate.service

Rationale

The ntpdate service may only be suitable for systems which are rebooted frequently enough that clock drift does not cause problems between reboots. In any event, the functionality of the ntpdate service is now available in the ntpd program and should be considered deprecated.

Disable Odd Job Daemon (oddjobd)xccdf_org.ssgproject.content_rule_service_oddjobd_disabled low

Disable Odd Job Daemon (oddjobd)

Rule IDxccdf_org.ssgproject.content_rule_service_oddjobd_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 381, Test attestation on 20121024 by DS

Description

The oddjobd service exists to provide an interface and access control mechanism through which specified privileged tasks can run tasks for unprivileged client applications. Communication with oddjobd through the system message bus. The oddjobd service can be disabled with the following command:

$ sudo systemctl disable oddjobd.service

Rationale

The oddjobd service may provide necessary functionality in some environments, and can be disabled if it is not needed. Execution of tasks by privileged programs, on behalf of unprivileged ones, has traditionally been a source of privilege escalation security issues.

Disable Portreserve (portreserve)xccdf_org.ssgproject.content_rule_service_portreserve_disabled low

Disable Portreserve (portreserve)

Rule IDxccdf_org.ssgproject.content_rule_service_portreserve_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, Test attestation on 20121024 by DS

Description

The portreserve service is a TCP port reservation utility that can be used to prevent portmap from binding to well known TCP ports that are required for other services. The portreserve service can be disabled with the following command:

$ sudo systemctl disable portreserve.service

Rationale

The portreserve service provides helpful functionality by preventing conflicting usage of ports in the reserved port range, but it can be disabled if not needed.

Enable Process Accounting (psacct)xccdf_org.ssgproject.content_rule_service_psacct_enabled low

Enable Process Accounting (psacct)

Rule IDxccdf_org.ssgproject.content_rule_service_psacct_enabled
Result
error
Time2016-07-11T14:24:57
Severitylow
Identifiers and References

identifiers: 

references:  AU-12, CM-7, Test attestation on 20121024 by DS

Description

The process accounting service, psacct, works with programs including acct and ac to allow system administrators to view user activity, such as commands issued by users of the system. The psacct service can be enabled with the following command:

$ sudo systemctl enable psacct.service

Rationale

The psacct service can provide administrators a convenient view into some user activities. However, it should be noted that the auditing system and its audit records provide more authoritative and comprehensive records.

Evaluation messages
info 
Fix execution completed and returned: 6
info 
Failed to execute operation: Access denied
Failed to start psacct.service: Unit psacct.service failed to load: No such file or directory.
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:
#
# Enable psacct.service for all systemd targets
#
systemctl enable psacct.service

#
# Start psacct.service if not currently running
#
systemctl start psacct.service
Disable Apache Qpid (qpidd)xccdf_org.ssgproject.content_rule_service_qpidd_disabled low

Disable Apache Qpid (qpidd)

Rule IDxccdf_org.ssgproject.content_rule_service_qpidd_disabled
Result
pass
Time2016-07-11T14:22:42
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 382

Description

The qpidd service provides high speed, secure, guaranteed delivery services. It is an implementation of the Advanced Message Queuing Protocol. By default the qpidd service will bind to port 5672 and listen for connection attempts. The qpidd service can be disabled with the following command:

$ sudo systemctl disable qpidd.service

Rationale

The qpidd service is automatically installed when the "base" package selection is selected during installation. The qpidd service listens for network connections, which increases the attack surface of the system. If the system is not intended to receive AMQP traffic, then the qpidd service is not needed and should be disabled or removed.

Disable Quota Netlink (quota_nld)xccdf_org.ssgproject.content_rule_service_quota_nld_disabled low

Disable Quota Netlink (quota_nld)

Rule IDxccdf_org.ssgproject.content_rule_service_quota_nld_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, Test attestation on 20121024 by DS

Description

The quota_nld service provides notifications to users of disk space quota violations. It listens to the kernel via a netlink socket for disk quota violations and notifies the appropriate user of the violation using D-Bus or by sending a message to the terminal that the user has last accessed. The quota_nld service can be disabled with the following command:

$ sudo systemctl disable quota_nld.service

Rationale

If disk quotas are enforced on the local system, then the quota_nld service likely provides useful functionality and should remain enabled. However, if disk quotas are not used or user notification of disk quota violation is not desired then there is no need to run this service.

Disable Network Router Discovery Daemon (rdisc)xccdf_org.ssgproject.content_rule_service_rdisc_disabled low

Disable Network Router Discovery Daemon (rdisc)

Rule IDxccdf_org.ssgproject.content_rule_service_rdisc_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), AC-4, CM-7, 382, Test attestation on 20121024 by DS

Description

The rdisc service implements the client side of the ICMP Internet Router Discovery Protocol (IRDP), which allows discovery of routers on the local subnet. If a router is discovered then the local routing table is updated with a corresponding default route. By default this daemon is disabled. The rdisc service can be disabled with the following command:

$ sudo systemctl disable rdisc.service

Rationale

General-purpose systems typically have their network and routing information configured statically by a system administrator. Workstations or some special-purpose systems often use DHCP (instead of IRDP) to retrieve dynamic network configuration information.

Disable Red Hat Network Service (rhnsd)xccdf_org.ssgproject.content_rule_service_rhnsd_disabled low

Disable Red Hat Network Service (rhnsd)

Rule IDxccdf_org.ssgproject.content_rule_service_rhnsd_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, 382, 1.2.4, Test attestation on 20121024 by DS

Description

The Red Hat Network service automatically queries Red Hat Network servers to determine whether there are any actions that should be executed, such as package updates. This only occurs if the system was registered to an RHN server or satellite and managed as such. The rhnsd service can be disabled with the following command:

$ sudo systemctl disable rhnsd.service

Rationale

Although systems management and patching is extremely important to system security, management by a system outside the enterprise enclave is not desirable for some environments. However, if the system is being managed by RHN or RHN Satellite Server the rhnsd daemon can remain on.

Disable Red Hat Subscription Manager Daemon (rhsmcertd)xccdf_org.ssgproject.content_rule_service_rhsmcertd_disabled low

Disable Red Hat Subscription Manager Daemon (rhsmcertd)

Rule IDxccdf_org.ssgproject.content_rule_service_rhsmcertd_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, Test attestation on 20121024 by DS

Description

The Red Hat Subscription Manager (rhsmcertd) periodically checks for changes in the entitlement certificates for a registered system and updates it accordingly. The rhsmcertd service can be disabled with the following command:

$ sudo systemctl disable rhsmcertd.service

Rationale

The rhsmcertd service can provide administrators with some additional control over which of their systems are entitled to particular subscriptions. However, for systems that are managed locally or which are not expected to require remote changes to their subscription status, it is unnecessary and can be disabled.

Disable Cyrus SASL Authentication Daemon (saslauthd)xccdf_org.ssgproject.content_rule_service_saslauthd_disabled low

Disable Cyrus SASL Authentication Daemon (saslauthd)

Rule IDxccdf_org.ssgproject.content_rule_service_saslauthd_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  AC-17(8), CM-7, Test attestation on 20121024 by DS

Description

The saslauthd service handles plaintext authentication requests on behalf of the SASL library. The service isolates all code requiring superuser privileges for SASL authentication into a single process, and can also be used to provide proxy authentication services to clients that do not understand SASL based authentication. The saslauthd service can be disabled with the following command:

$ sudo systemctl disable saslauthd.service

Rationale

The saslauthd service provides essential functionality for performing authentication in some directory environments, such as those which use Kerberos and LDAP. For others, however, in which only local files may be consulted, it is not necessary and should be disabled.

Disable SMART Disk Monitoring Service (smartd)xccdf_org.ssgproject.content_rule_service_smartd_disabled low

Disable SMART Disk Monitoring Service (smartd)

Rule IDxccdf_org.ssgproject.content_rule_service_smartd_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, Test attestation on 20121024 by DS

Description

SMART (Self-Monitoring, Analysis, and Reporting Technology) is a feature of hard drives that allows them to detect symptoms of disk failure and relay an appropriate warning. The smartd service can be disabled with the following command:

$ sudo systemctl disable smartd.service

Rationale

SMART can help protect against denial of service due to failing hardware. Nevertheless, if it is not needed or the system's drives are not SMART-capable (such as solid state drives), it can be disabled.

Disable System Statistics Reset Service (sysstat)xccdf_org.ssgproject.content_rule_service_sysstat_disabled low

Disable System Statistics Reset Service (sysstat)

Rule IDxccdf_org.ssgproject.content_rule_service_sysstat_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, Test attestation on 20121024 by DS

Description

The sysstat service resets various I/O and CPU performance statistics to zero in order to begin counting from a fresh state at boot time. The sysstat service can be disabled with the following command:

$ sudo systemctl disable sysstat.service

Rationale

By default the sysstat service merely runs a program at boot to reset the statistics, which can be retrieved using programs such as sar and sadc. These may provide useful insight into system operation, but unless used this service can be disabled.

Enable cron Servicexccdf_org.ssgproject.content_rule_service_crond_enabled medium

Enable cron Service

Rule IDxccdf_org.ssgproject.content_rule_service_crond_enabled
Result
pass
Time2016-07-11T14:22:43
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 6.1.2, Test attestation on 20121024 by DS

Description

The crond service is used to execute commands at preconfigured times. It is required by almost all systems to perform necessary maintenance tasks, such as notifying root of system activity. The crond service can be enabled with the following command:

$ sudo systemctl enable crond.service

Rationale

Due to its usage for maintenance and security-supporting tasks, enabling the cron daemon is essential.

Disable anacron Servicexccdf_org.ssgproject.content_rule_disable_anacron low

Disable anacron Service

Rule IDxccdf_org.ssgproject.content_rule_disable_anacron
Result
notchecked
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The cronie-anacron package, which provides anacron functionality, is installed by default. The cronie-anacron package can be removed with the following command:

$ sudo yum erase cronie-anacron

Rationale

The anacron service provides cron functionality for systems such as laptops and workstations that may be shut down during the normal times that cron jobs are scheduled to run. On systems which do not require this additional functionality, anacron could needlessly increase the possible attack surface for an intruder.

Evaluation messages
info 
No candidate or applicable check found.
Disable At Service (atd)xccdf_org.ssgproject.content_rule_service_atd_disabled low

Disable At Service (atd)

Rule IDxccdf_org.ssgproject.content_rule_service_atd_disabled
Result
pass
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 381

Description

The at and batch commands can be used to schedule tasks that are meant to be executed only once. This allows delayed execution in a manner similar to cron, except that it is not recurring. The daemon atd keeps track of tasks scheduled via at and batch, and executes them at the specified time. The atd service can be disabled with the following command:

$ sudo systemctl disable atd.service

Rationale

The atd service could be used by an unsophisticated insider to carry out activities outside of a normal login session, which could complicate accountability. Furthermore, the need to schedule tasks with at or batch is not common.

Allow Only SSH Protocol 2xccdf_org.ssgproject.content_rule_sshd_allow_only_protocol2 high

Allow Only SSH Protocol 2

Rule IDxccdf_org.ssgproject.content_rule_sshd_allow_only_protocol2
Result
pass
Time2016-07-11T14:22:44
Severityhigh
Identifiers and References

identifiers: 

references:  AC-17(8).1(ii), IA-5(1)(c), 197, 366, 6.2.1, SRG-OS-000074-GPOS-00042, SRG-OS-000480-GPOS-00227, RHEL-07-040590, Test attestation on 20121024 by DS

Description

Only SSH protocol version 2 connections should be permitted. The default setting in /etc/ssh/sshd_config is correct, and can be verified by ensuring that the following line appears:

Protocol 2

Rationale

SSH protocol version 1 is an insecure implementation of the SSH protocol and has many well-known vulnerability exploits. Exploits of the SSH daemon could provide immediate root access to the system.

Limit Users' SSH Accessxccdf_org.ssgproject.content_rule_sshd_limit_user_access low

Limit Users' SSH Access

Rule IDxccdf_org.ssgproject.content_rule_sshd_limit_user_access
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  AC-3

Description

By default, the SSH configuration allows any user with an account to access the system. In order to specify the users that are allowed to login via SSH and deny all other users, add or correct the following line in the /etc/ssh/sshd_config file:

DenyUsers USER1 USER2
Where USER1 and USER2 are valid user names.

Rationale

Specifying which accounts are allowed SSH access into the system reduces the possibility of unauthorized access to the system.

Evaluation messages
info 
No candidate or applicable check found.
Disable GSSAPI Authenticationxccdf_org.ssgproject.content_rule_sshd_disable_gssapi_auth medium

Disable GSSAPI Authentication

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_gssapi_auth
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(c), 368, 318, 1812, 1813, 1814, SRG-OS-000364-GPOS-00151, RHEL-07-040660

Description

Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like GSSAPI. To disable GSSAPI authentication, add or correct the following line in the /etc/ssh/sshd_config file:

GSSAPIAuthentication no

Rationale

GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system's GSSAPI to remote hosts, increasing the attack surface of the system.

Disable Kerberos Authenticationxccdf_org.ssgproject.content_rule_sshd_disable_kerb_auth medium

Disable Kerberos Authentication

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_kerb_auth
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(c), 368, 318, 1812, 1813, 1814, SRG-OS-000364-GPOS-00151, RHEL-07-040670

Description

Unless needed, SSH should not permit extraneous or unnecessary authentication mechanisms like Kerberos. To disable Kerberos authentication, add or correct the following line in the /etc/ssh/sshd_config file:

KerberosAuthentication no

Rationale

Kerberos authentication for SSH is often implemented using GSSAPI. If Kerberos is enabled through SSH, the SSH daemon provides a means of access to the system's Kerberos implementation. Vulnerabilities in the system's Kerberos implementations may be subject to exploitation.

Enable Use of StictModesxccdf_org.ssgproject.content_rule_sshd_enable_strictmodes medium

Enable Use of StictModes

Rule IDxccdf_org.ssgproject.content_rule_sshd_enable_strictmodes
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040680

Description

SSHs StrictModes option checks file and ownership permissions in the user's home directory .ssh folder before accepting login. If world- writable permissions are found, logon is rejected. To enable StrictModes in SSH, add or correct the following line in the /etc/ssh/sshd_config file:

StrictModes yes

Rationale

If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user.

Enable Use of Privilege Separationxccdf_org.ssgproject.content_rule_sshd_use_priv_separation medium

Enable Use of Privilege Separation

Rule IDxccdf_org.ssgproject.content_rule_sshd_use_priv_separation
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040690

Description

When enabled, SSH will create an unprivileged child process that has the privilege of the authenticated user. To enable privilege separation in SSH, add or correct the following line in the /etc/ssh/sshd_config file:

UsePrivilegeSeparation yes

Rationale

SSH daemon privilege separation causes the SSH process to drop root privileges when not needed which would decrease the impact of software vulnerabilities in the unprivileged section.

Disable Compression Or Set Compression to delayedxccdf_org.ssgproject.content_rule_sshd_disable_compression medium

Disable Compression Or Set Compression to delayed

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_compression
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040700

Description

Compression is useful for slow network connections over long distances but can cause performance issues on local LANs. If use of compression is required, it should be enabled only after a user has authenticated; otherwise , it should be disabled. To disable compression or delay compression until after a user has successfully authenticated, add or correct the following line in the /etc/ssh/sshd_config file:

Compression no
or
Compression delayed

Rationale

If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially wih root privileges.

Print Last Logxccdf_org.ssgproject.content_rule_sshd_print_last_log low

Print Last Log

Rule IDxccdf_org.ssgproject.content_rule_sshd_print_last_log
Result
fail
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  AC-9, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040300

Description

When enabled, SSH will display the date and time of the last successful account logon. To enable LastLog in SSH, add or correct the following line in the /etc/ssh/sshd_config file:

PrintLastLog yes

Rationale

Providing users feedback on when account accesses last occurred facilitates user recognition and reporting of unauthorized account use.

Set SSH Idle Timeout Intervalxccdf_org.ssgproject.content_rule_sshd_set_idle_timeout low

Set SSH Idle Timeout Interval

Rule IDxccdf_org.ssgproject.content_rule_sshd_set_idle_timeout
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  AC-2(5), SA-8(i), AC-12, 1133, 2361, SRG-OS-000163-GPOS-00072, SRG-OS-000279-GPOS-00109, RHEL-07-040190, Req-8.1.8, 6.2.12, Test attestation on 20121024 by DS

Description

SSH allows administrators to set an idle timeout interval. After this interval has passed, the idle user will be automatically logged out.

To set an idle timeout interval, edit the following line in /etc/ssh/sshd_config as follows:

ClientAliveInterval interval
The timeout interval is given in seconds. To have a timeout of 10 minutes, set interval to 600.

If a shorter timeout has already been set for the login shell, that value will preempt any SSH setting made here. Keep in mind that some processes may stop SSH from correctly detecting that the user is idle.

Rationale

Terminating an idle ssh session within a short time period reduces the window of opportunity for unauthorized personnel to take control of a management session enabled on the console or console port that has been let unattended.

Set SSH Client Alive Countxccdf_org.ssgproject.content_rule_sshd_set_keepalive low

Set SSH Client Alive Count

Rule IDxccdf_org.ssgproject.content_rule_sshd_set_keepalive
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  AC-2(5), SA-8, AC-12, 1133, 2361, SRG-OS-000163-GPOS-00072, SRG-OS-000279-GPOS-00109, RHEL-07-TBD, 6.2.12, Test attestation on 20121024 by DS

Description

To ensure the SSH idle timeout occurs precisely when the ClientAliveCountMax is set, edit /etc/ssh/sshd_config as follows:

ClientAliveCountMax 0

Rationale

This ensures a user login will be terminated as soon as the ClientAliveCountMax is reached.

Disable SSH Support for .rhosts Filesxccdf_org.ssgproject.content_rule_sshd_disable_rhosts medium

Disable SSH Support for .rhosts Files

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_rhosts
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-3, http://iase.disa.mil/stigs/cci/Pages/index.aspx, 6.2.6

Description

SSH can emulate the behavior of the obsolete rsh command in allowing users to enable insecure access to their accounts via .rhosts files.

To ensure this behavior is disabled, add or correct the following line in /etc/ssh/sshd_config:

IgnoreRhosts yes

Rationale

SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.

Disable Host-Based Authenticationxccdf_org.ssgproject.content_rule_disable_host_auth medium

Disable Host-Based Authentication

Rule IDxccdf_org.ssgproject.content_rule_disable_host_auth
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-3, CM-6(b), 366, SRG-OS-000480-GPOS-00229, RHEL-07-010442, 6.2.7, Test attestation on 20121024 by DS

Description

SSH's cryptographic host-based authentication is more secure than .rhosts authentication. However, it is not recommended that hosts unilaterally trust one another, even within an organization.

To disable host-based authentication, add or correct the following line in /etc/ssh/sshd_config:

HostbasedAuthentication no

Rationale

SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.

Enable Encrypted X11 Fordwardingxccdf_org.ssgproject.content_rule_enable_x11_forwarding high

Enable Encrypted X11 Fordwarding

Rule IDxccdf_org.ssgproject.content_rule_enable_x11_forwarding
Result
pass
Time2016-07-11T14:22:44
Severityhigh
Identifiers and References

identifiers: 

references:  CM-2(1)(b), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040540

Description

By default, remote X11 connections are not encrypted when initiated by users. SSH has the capability to encrypt remote X11 connections when SSH's X11Forwarding option is enabled.

To enable X11 Forwarding, add or correct the following line in /etc/ssh/sshd_config:

X11Forwarding yes

Rationale

Open X displays allow an attacker to capture keystrokes and to execute commands remotely.

Disable SSH Access via Empty Passwordsxccdf_org.ssgproject.content_rule_sshd_disable_empty_passwords high

Disable SSH Access via Empty Passwords

Rule IDxccdf_org.ssgproject.content_rule_sshd_disable_empty_passwords
Result
pass
Time2016-07-11T14:22:44
Severityhigh
Identifiers and References

identifiers: 

references:  AC-3, CM-6(b), 366, SRG-OS-000480-GPOS-00229, RHEL-07-010440, Test attestation on 20121024 by DS

Description

To explicitly disallow SSH login from accounts with empty passwords, add or correct the following line in /etc/ssh/sshd_config:

PermitEmptyPasswords no

Any accounts with empty passwords should be disabled immediately, and PAM configuration should prevent users from being able to assign themselves empty passwords.

Rationale

Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere.

Enable SSH Warning Bannerxccdf_org.ssgproject.content_rule_sshd_enable_warning_banner medium

Enable SSH Warning Banner

Rule IDxccdf_org.ssgproject.content_rule_sshd_enable_warning_banner
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-8(a), AC-8(b), AC-8(c)(1), AC-8(c)(2), AC-8(c)(3), 48, 50, 1384, 1385, 1386, 1387, 1388, SRG-OS-000023-GPOS-00006, SRG-OS-000024-GPOS-00007, SRG-OS-000228-GPOS-00088, 6.2.14, RHEL-07-040170, Test attestation on 20121024 by DS

Description

To enable the warning banner and ensure it is consistent across the system, add or correct the following line in /etc/ssh/sshd_config:

Banner /etc/issue
Another section contains information on how to create an appropriate system-wide warning banner.

Rationale

The warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. Alternatively, systems whose ownership should not be obvious should ensure usage of a banner that does not provide easy attribution.

Do Not Allow SSH Environment Optionsxccdf_org.ssgproject.content_rule_sshd_do_not_permit_user_env medium

Do Not Allow SSH Environment Options

Rule IDxccdf_org.ssgproject.content_rule_sshd_do_not_permit_user_env
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-6(b), 366, SRG-OS-000480-GPOS-00229, RHEL-07-010441, 6.2.10, Test attestation on 20121024 by DS

Description

To ensure users are not able to override environment options to the SSH daemon, add or correct the following line in /etc/ssh/sshd_config:

PermitUserEnvironment no

Rationale

SSH environment options potentially allow users to bypass access restriction in some configurations.

Use Only Approved Ciphersxccdf_org.ssgproject.content_rule_sshd_use_approved_ciphers medium

Use Only Approved Ciphers

Rule IDxccdf_org.ssgproject.content_rule_sshd_use_approved_ciphers
Result
error
Time2016-07-11T14:24:57
Severitymedium
Identifiers and References

identifiers: 

references:  AC-3, AC-17(2), AU-10(5), CM-6(b), IA-5(1)(c), IA-7, 68, 366, 803, SRG-OS-000033-GPOS-00014, SRG-OS-000120-GPOS-00061, SRG-OS-000125-GPOS-00065, SRG-OS-000250-GPOS-00093, SRG-OS-000393-GPOS-00173, RHEL-07-040110, 6.2.11, Test attestation on 20121024 by DS

Description

Limit the ciphers to those algorithms which are FIPS-approved. Counter (CTR) mode is also preferred over cipher-block chaining (CBC) mode. The following line in /etc/ssh/sshd_config demonstrates use of FIPS-approved ciphers:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr
The man page sshd_config(5) contains a list of supported ciphers.

Rationale

Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and system data may be compromised.
Operating systems utilizing encryption are required to use FIPS-compliant mechanisms for authenticating to cryptographic modules.
FIPS 140-2 is the current standard for validating that mechanisms used to access cryptographic modules utilize authentication that meets industry and government requirements. For government systems, this allows Security Levels 1, 2, 3, or 4 for use on Red Hat Enterprise Linux.

Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:

function replace_or_append {
  local config_file=$1
  local key=$2
  local value=$3
  local cce=$4
  local format=$5

  # Check sanity of the input
  if [ $# -lt "3" ]
  then
        echo "Usage: replace_or_append 'config_file_location' 'key_to_search' 'new_value'"
        echo
        echo "If symlinks need to be taken into account, add yes/no to the last argument"
        echo "to allow to 'follow_symlinks'."
        echo "Aborting."
        exit 1
  fi

  # Test if the config_file is a symbolic link. If so, use --follow-symlinks with sed.
  # Otherwise, regular sed command will do.
  if test -L $config_file; then
    sed_command="sed -i --follow-symlinks"
  else
    sed_command="sed -i"
  fi

  # Test that the cce arg is not empty or does not equal CCENUM.
  # If CCENUM exists, it means that there is no CCE assigned.
  if ! [ "x$cce" = x ] && [ "$cce" != 'CCENUM' ]; then
    cce="CCE-${cce}"
  else
    cce="CCE"
  fi

  # Strip any search characters in the key arg so that the key can be replaced without
  # adding any search characters to the config file.
  stripped_key=${key//[!a-zA-Z]/}

  # If there is no print format specified in the last arg, use the default format.
  if ! [ "x$format" = x ] ; then
    printf -v formatted_output "$format" $stripped_key $value
  else
    formatted_output="$stripped_key = $value"
  fi

  # If the key exists, change it. Otherwise, add it to the config_file.
  if `grep -qi $key $config_file` ; then
    $sed_command "s/$key.*/$formatted_output/g" $config_file
  else
    echo -ne "\n# Per $cce: Set $formatted_output in $config_file" >> $config_file
    echo -ne "\n$formatted_output" >> $config_file
  fi

}

replace_or_append '/etc/ssh/sshd_config' '^Ciphers' 'aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc,aes192-cbc,aes256-cbc' 'CCENUM' '%s %s'
Use Only FIPS Approved MACsxccdf_org.ssgproject.content_rule_sshd_use_approved_macs medium

Use Only FIPS Approved MACs

Rule IDxccdf_org.ssgproject.content_rule_sshd_use_approved_macs
Result
error
Time2016-07-11T14:24:57
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(2), IA-7, SC-13, 68, 803, 1453, 2449, 2450, SRG-OS-000250-GPOS-00093, RHEL-07-040620

Description

Limit the MACs to those hash algorithms which are FIPS-approved. The following line in /etc/ssh/sshd_config demonstrates use of FIPS-approved MACs:

MACs hmac-sha2-512,hmac-sha2-256
The man page sshd_config(5) contains a list of supported MACs.

Rationale

DoD Information Systems are required to use FIPS-approved cryptographic hash functions. The only SSHv2 hash algorithms meeting this requirement is SHA2.

Evaluation messages
info 
Fix execution completed and returned: 0
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:
grep -qi ^MACs /etc/ssh/sshd_config && \
  sed -i "s/MACs.*/MACs hmac-sha2-512,hmac-sha2-256,hmac-sha1/gI" /etc/ssh/sshd_config
if ! [ $? -eq 0 ]; then
    echo "MACs hmac-sha2-512,hmac-sha2-256,hmac-sha1" >> /etc/ssh/sshd_config
fi
Install the OpenSSH Server Packagexccdf_org.ssgproject.content_rule_package_openssh-server_installed medium

Install the OpenSSH Server Package

Rule IDxccdf_org.ssgproject.content_rule_package_openssh-server_installed
Result
pass
Time2016-07-11T14:22:43
Severitymedium
Identifiers and References

identifiers: 

references:  SC-8, 2418, 2420, 2421, 2422, SRG-OS-000423-GPOS-00187, SRG-OS-000423-GPOS-00188, SRG-OS-000423-GPOS-00189, SRG-OS000423-GPOS-00190, RHEL-07-040260

Description

The openssh-server package should be installed. The openssh-server package can be installed with the following command:

$ sudo yum install openssh-server

Rationale

Without protection of the transmitted information, confidentiality, and integrity may be compromised because unprotected communications can be intercepted and either read or altered.

Enable the OpenSSH Servicexccdf_org.ssgproject.content_rule_service_sshd_enabled medium

Enable the OpenSSH Service

Rule IDxccdf_org.ssgproject.content_rule_service_sshd_enabled
Result
pass
Time2016-07-11T14:22:43
Severitymedium
Identifiers and References

identifiers: 

references:  SC-8, 2418, 2420, 2421, 2422, SRG-OS-000423-GPOS-00187, SRG-OS-000423-GPOS-00188, SRG-OS-000423-GPOS-00189, SRG-OS000423-GPOS-00190, RHEL-07-TBD

Description

The SSH server service, sshd, is commonly needed. The sshd service can be enabled with the following command:

$ sudo systemctl enable sshd.service

Rationale

Without protection of the transmitted information, confidentiality, and integrity may be compromised because unprotected communications can be intercepted and either read or altered.

Disable SSH Server If Possible (Unusual)xccdf_org.ssgproject.content_rule_service_sshd_disabled low

Disable SSH Server If Possible (Unusual)

Rule IDxccdf_org.ssgproject.content_rule_service_sshd_disabled
Result
notselected
Time2016-07-11T14:22:43
Severitylow
Identifiers and References

identifiers: 

references:  Test attestation on 20121024 by DS

Description

The SSH server service, sshd, is commonly needed. However, if it can be disabled, do so. The sshd service can be disabled with the following command:

$ sudo systemctl disable sshd.service
This is unusual, as SSH is a common method for encrypted and authenticated remote access.

Verify Permissions on SSH Server Public *.pub Key Filesxccdf_org.ssgproject.content_rule_file_permissions_sshd_pub_key medium

Verify Permissions on SSH Server Public *.pub Key Files

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_sshd_pub_key
Result
pass
Time2016-07-11T14:22:43
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040640

Description

To properly set the permissions of /etc/ssh/*.pub, run the command:

$ sudo chmod 0644 /etc/ssh/*.pub

Rationale

If a public host key file is modified by an unauthorized user, the SSH service may be compromised.

Verify Permissions on SSH Server Private *_key Key Filesxccdf_org.ssgproject.content_rule_file_permissions_sshd_private_key medium

Verify Permissions on SSH Server Private *_key Key Files

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_sshd_private_key
Result
fail
Time2016-07-11T14:22:43
Severitymedium
Identifiers and References

identifiers: 

references:  AC-6, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040650

Description

To properly set the permissions of /etc/ssh/*_key, run the command:

$ sudo chmod 0600 /etc/ssh/*_key

Rationale

If an unauthorized user obtains the private SSH host key file, the host could be impersonated.

Remove SSH Server firewalld Firewall exception (Unusual)xccdf_org.ssgproject.content_rule_firewalld_sshd_disabled low

Remove SSH Server firewalld Firewall exception (Unusual)

Rule IDxccdf_org.ssgproject.content_rule_firewalld_sshd_disabled
Result
fail
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

By default, inbound connections to SSH's port are allowed. If the SSH server is not being used, this exception should be removed from the firewall configuration.

To configure firewalld to not allow access, run the following command(s):

Rationale

If inbound SSH connections are not expected, disallowing access to the SSH port will avoid possible exploitation of the port by an attacker.

Install the SSSD Packagexccdf_org.ssgproject.content_rule_package_sssd_installed medium

Install the SSSD Package

Rule IDxccdf_org.ssgproject.content_rule_package_sssd_installed
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(10), TBD, TBD, RHEL-07-TBD

Description

The sssd package should be installed. The sssd package can be installed with the following command:

$ sudo yum install sssd

Rationale

Enable the SSSD Servicexccdf_org.ssgproject.content_rule_service_sssd_enabled medium

Enable the SSSD Service

Rule IDxccdf_org.ssgproject.content_rule_service_sssd_enabled
Result
error
Time2016-07-11T14:24:58
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(10), TBD, TBD, RHEL-07-TBD

Description

The SSSD service should be enabled. The sssd service can be enabled with the following command:

$ sudo systemctl enable sssd.service

Rationale

Evaluation messages
info 
Fix execution completed and returned: 6
info 
Failed to execute operation: Access denied
Failed to start sssd.service: Unit sssd.service failed to load: No such file or directory.
info 
Failed to verify applied fix: Checking engine returns: fail
Remediation script:
#
# Disable sssd.service for all systemd targets
#
systemctl enable sssd.service

#
# Stop sssd.service if currently running
#
systemctl start sssd.service
Configure SSSD's Memory Cache to Expirexccdf_org.ssgproject.content_rule_sssd_memcache_timeout medium

Configure SSSD's Memory Cache to Expire

Rule IDxccdf_org.ssgproject.content_rule_sssd_memcache_timeout
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(13), 2007, SRG-OS-000383-GPOS-00166, RHEL-07-010400

Description

SSSD's memory cache should be configured to set to expire records after 1 day. To configure SSSD to expire memory cache, set memcache_timeout to 86400 under the [nss] section in /etc/sssd/sssd.conf. For example:

[nss]
memcache_timeout = 86400

Rationale

If cached authentication information is out-of-date, the validity of the authentication information may be questionable.

Configure SSSD to Expire Offline Credentialsxccdf_org.ssgproject.content_rule_sssd_offline_cred_expiration medium

Configure SSSD to Expire Offline Credentials

Rule IDxccdf_org.ssgproject.content_rule_sssd_offline_cred_expiration
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(13), 2007, SRG-OS-000383-GPOS-00166, RHEL-07-010401

Description

SSSD should be configured to expire offline credentials after 1 day. To configure SSSD to expire offline credentials, set offline_credentials_expiration to 1 under the [nss] section in /etc/sssd/sssd.conf. For example:

[nss]
offline_credentials_expiration = 1

Rationale

If cached authentication information is out-of-date, the validity of the authentication information may be questionable.

Configure SSSD to Expire SSH Known Hostsxccdf_org.ssgproject.content_rule_sssd_ssh_known_hosts_timeout medium

Configure SSSD to Expire SSH Known Hosts

Rule IDxccdf_org.ssgproject.content_rule_sssd_ssh_known_hosts_timeout
Result
fail
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  IA-5(13), 2007, SRG-OS-000383-GPOS-00166, RHEL-07-010402

Description

SSSD should be configured to expire keys from known SSH hosts after 1 day. To configure SSSD to known SSH hosts, set ssh_known_hosts_timeout to 86400 under the [nss] section in /etc/sssd/sssd.conf. For example:

[nss]
ssh_known_hosts_timeout = 86400

Rationale

If cached authentication information is out-of-date, the validity of the authentication information may be questionable.

Disable X Windows Startup By Setting Default Targetxccdf_org.ssgproject.content_rule_xwindows_runlevel_setting medium

Disable X Windows Startup By Setting Default Target

Rule IDxccdf_org.ssgproject.content_rule_xwindows_runlevel_setting
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8).1(ii), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040561, Test attestation on 20121025 by DS

Description

Systems that do not require a graphical user interface should only boot by default into multi-user.target mode. This prevents accidental booting of the system into a graphical.target mode. Setting the system's default target to multi-user.target will prevent automatic startup of the X server. To do so, run:

$ systemctl set-default multi-user.target
You should see the following output:
rm '/etc/systemd/system/default.target'
ln -s '/usr/lib/systemd/system/multi-user.target' '/etc/systemd/system/default.target'

Rationale

Services that are not required for system and application processes must not be active to decrease the attack surface of the system. X windows has a long history of security vulnerabilities and should not be used unless approved and documented.

Remove the X Windows Package Groupxccdf_org.ssgproject.content_rule_package_xorg-x11-server-common_removed medium

Remove the X Windows Package Group

Rule IDxccdf_org.ssgproject.content_rule_package_xorg-x11-server-common_removed
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-17(8).1(ii), 366, 3.2, SRG-OS-000480-GPOS-00227, RHEL-07-040560, Test attestation on 20121025 by DS

Description

By removing the xorg-x11-server-common package, the system no longer has X Windows installed. If X Windows is not installed then the system cannot boot into graphical user mode. This prevents the system from being accidentally or maliciously booted into a graphical.target mode. To do so, run the following command:

$ sudo yum groupremove "X Window System"
$ sudo yum remove xorg-x11-server-common

Rationale

Unnecessary service packages must not be installed to decrease the attack surface of the system. X windows has a long history of security vulnerabilities and should not be installed unless approved and documented.

Disable Avahi Server Softwarexccdf_org.ssgproject.content_rule_service_avahi-daemon_disabled low

Disable Avahi Server Software

Rule IDxccdf_org.ssgproject.content_rule_service_avahi-daemon_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 366, 3.3

Description

The avahi-daemon service can be disabled with the following command:

$ sudo systemctl disable avahi-daemon.service

Rationale

Because the Avahi daemon service keeps an open network port, it is subject to network attacks. Its functionality is convenient but is only appropriate if the local network can be trusted.

Serve Avahi Only via Required Protocolxccdf_org.ssgproject.content_rule_avahi_ip_only low

Serve Avahi Only via Required Protocol

Rule IDxccdf_org.ssgproject.content_rule_avahi_ip_only
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

If you are using only IPv4, edit /etc/avahi/avahi-daemon.conf and ensure the following line exists in the [server] section:

use-ipv6=no
Similarly, if you are using only IPv6, disable IPv4 sockets with the line:
use-ipv4=no

Check Avahi Responses' TTL Fieldxccdf_org.ssgproject.content_rule_avahi_check_ttl low

Check Avahi Responses' TTL Field

Rule IDxccdf_org.ssgproject.content_rule_avahi_check_ttl
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

To make Avahi ignore packets unless the TTL field is 255, edit /etc/avahi/avahi-daemon.conf and ensure the following line appears in the [server] section:

check-response-ttl=yes

Rationale

This helps to ensure that only mDNS responses from the local network are processed, because the TTL field in a packet is decremented from its initial value of 255 whenever it is routed from one network to another. Although a properly-configured router or firewall should not allow mDNS packets into the local network at all, this option provides another check to ensure they are not permitted.

Prevent Other Programs from Using Avahi's Portxccdf_org.ssgproject.content_rule_avahi_prevent_port_sharing low

Prevent Other Programs from Using Avahi's Port

Rule IDxccdf_org.ssgproject.content_rule_avahi_prevent_port_sharing
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

To prevent other mDNS stacks from running, edit /etc/avahi/avahi-daemon.conf and ensure the following line appears in the [server] section:

disallow-other-stacks=yes

Rationale

This helps ensure that only Avahi is responsible for mDNS traffic coming from that port on the system.

Disable Avahi Publishingxccdf_org.ssgproject.content_rule_avahi_disable_publishing low

Disable Avahi Publishing

Rule IDxccdf_org.ssgproject.content_rule_avahi_disable_publishing
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

To prevent other mDNS stacks from running, edit /etc/avahi/avahi-daemon.conf and ensure the following line appears in the [server] section:

disallow-other-stacks=yes

Rationale

This helps ensure that only Avahi is responsible for mDNS traffic coming from that port on the system.

Restrict Information Published by Avahixccdf_org.ssgproject.content_rule_avahi_restrict_published_information low

Restrict Information Published by Avahi

Rule IDxccdf_org.ssgproject.content_rule_avahi_restrict_published_information
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

If it is necessary to publish some information to the network, it should not be joined by any extraneous information, or by information supplied by a non-trusted source on the system. Prevent user applications from using Avahi to publish services by adding or correcting the following line in the [publish] section:

disable-user-service-publishing=yes
Implement as many of the following lines as possible, to restrict the information published by Avahi.
publish-addresses=no
publish-hinfo=no
publish-workstation=no
publish-domain=no
Inspect the files in the directory /etc/avahi/services/. Unless there is an operational need to publish information about each of these services, delete the corresponding file.

Rationale

These options prevent publishing attempts from succeeding, and can be applied even if publishing is disabled entirely via disable-publishing. Alternatively, these can be used to restrict the types of published information in the event that some information must be published.

Disable Printer Browsing Entirely if Possiblexccdf_org.ssgproject.content_rule_cups_disable_browsing low

Disable Printer Browsing Entirely if Possible

Rule IDxccdf_org.ssgproject.content_rule_cups_disable_browsing
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

By default, CUPS listens on the network for printer list broadcasts on UDP port 631. This functionality is called printer browsing. To disable printer browsing entirely, edit the CUPS configuration file, located at /etc/cups/cupsd.conf, to include the following:

Browsing Off

Rationale

The CUPS print service can be configured to broadcast a list of available printers to the network. Other machines on the network, also running the CUPS print service, can be configured to listen to these broadcasts and add and configure these printers for immediate use. By disabling this browsing capability, the machine will no longer generate or receive such broadcasts.

Disable Print Server Capabilitiesxccdf_org.ssgproject.content_rule_cups_disable_printserver low

Disable Print Server Capabilities

Rule IDxccdf_org.ssgproject.content_rule_cups_disable_printserver
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

To prevent remote users from potentially connecting to and using locally configured printers, disable the CUPS print server sharing capabilities. To do so, limit how the server will listen for print jobs by removing the more generic port directive from /etc/cups/cupsd.conf:

Port 631
and replacing it with the Listen directive:
Listen localhost:631
This will prevent remote users from printing to locally configured printers while still allowing local users on the machine to print normally.

Rationale

By default, locally configured printers will not be shared over the network, but if this functionality has somehow been enabled, these recommendations will disable it again. Be sure to disable outgoing printer list broadcasts, or remote users will still be able to see the locally configured printers, even if they cannot actually print to them. To limit print serving to a particular set of users, use the Policy directive.

Disable the CUPS Servicexccdf_org.ssgproject.content_rule_service_cups_disabled low

Disable the CUPS Service

Rule IDxccdf_org.ssgproject.content_rule_service_cups_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 3.4

Description

The cups service can be disabled with the following command:

$ sudo systemctl disable cups.service

Rationale

Turn off unneeded services to reduce attack surface.

Disable DHCP Servicexccdf_org.ssgproject.content_rule_service_dhcpd_disabled medium

Disable DHCP Service

Rule IDxccdf_org.ssgproject.content_rule_service_dhcpd_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 366, Test attestation on 20121024 by DS

Description

The dhcpd service should be disabled on any system that does not need to act as a DHCP server. The dhcpd service can be disabled with the following command:

$ sudo systemctl disable dhcpd.service

Rationale

Unmanaged or unintentionally activated DHCP servers may provide faulty information to clients, interfering with the operation of a legitimate site DHCP server if there is one.

Uninstall DHCP Server Packagexccdf_org.ssgproject.content_rule_package_dhcp_removed medium

Uninstall DHCP Server Package

Rule IDxccdf_org.ssgproject.content_rule_package_dhcp_removed
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 366, 3.5, Test attestation on 20121024 by DS

Description

If the system does not need to act as a DHCP server, the dhcp package can be uninstalled. The dhcp package can be removed with the following command:

$ sudo yum erase dhcp

Rationale

Removing the DHCP server ensures that it cannot be easily or accidentally reactivated and disrupt network operation.

Do Not Use Dynamic DNSxccdf_org.ssgproject.content_rule_dhcp_server_disable_ddns low

Do Not Use Dynamic DNS

Rule IDxccdf_org.ssgproject.content_rule_dhcp_server_disable_ddns
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

To prevent the DHCP server from receiving DNS information from clients, edit /etc/dhcp/dhcpd.conf, and add or correct the following global option:

ddns-update-style none;

Rationale

The Dynamic DNS protocol is used to remotely update the data served by a DNS server. DHCP servers can use Dynamic DNS to publish information about their clients. This setup carries security risks, and its use is not recommended. If Dynamic DNS must be used despite the risks it poses, it is critical that Dynamic DNS transactions be protected using TSIG or some other cryptographic authentication mechanism. See dhcpd.conf(5) for more information about protecting the DHCP server from passing along malicious DNS data from its clients.

Warnings
warning  The ddns-update-style option controls only whether the DHCP server will attempt to act as a Dynamic DNS client. As long as the DNS server itself is correctly configured to reject DDNS attempts, an incorrect ddns-update-style setting on the client is harmless (but should be fixed as a best practice).
Evaluation messages
info 
No candidate or applicable check found.
Deny Decline Messagesxccdf_org.ssgproject.content_rule_dhcp_server_deny_decline low

Deny Decline Messages

Rule IDxccdf_org.ssgproject.content_rule_dhcp_server_deny_decline
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Edit /etc/dhcp/dhcpd.conf and add or correct the following global option to prevent the DHCP server from responding the DHCPDECLINE messages, if possible:

deny declines;

Rationale

The DHCPDECLINE message can be sent by a DHCP client to indicate that it does not consider the lease offered by the server to be valid. By issuing many DHCPDECLINE messages, a malicious client can exhaust the DHCP server's pool of IP addresses, causing the DHCP server to forget old address allocations.

Evaluation messages
info 
No candidate or applicable check found.
Deny BOOTP Queriesxccdf_org.ssgproject.content_rule_dhcp_server_deny_bootp low

Deny BOOTP Queries

Rule IDxccdf_org.ssgproject.content_rule_dhcp_server_deny_bootp
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Unless your network needs to support older BOOTP clients, disable support for the bootp protocol by adding or correcting the global option:

deny bootp;

Rationale

The bootp option tells dhcpd to respond to BOOTP queries. If support for this simpler protocol is not needed, it should be disabled to remove attack vectors against the DHCP server.

Evaluation messages
info 
No candidate or applicable check found.
Configure Loggingxccdf_org.ssgproject.content_rule_dhcp_server_configure_logging low

Configure Logging

Rule IDxccdf_org.ssgproject.content_rule_dhcp_server_configure_logging
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  AU-12

Description

Ensure that the following line exists in /etc/rsyslog.conf:

daemon.*           /var/log/daemon.log
Configure logwatch or other log monitoring tools to summarize error conditions reported by the dhcpd process.

Rationale

By default, dhcpd logs notices to the daemon facility. Sending all daemon messages to a dedicated log file is part of the syslog configuration outlined in the Logging and Auditing section

Evaluation messages
info 
No candidate or applicable check found.
Disable DHCP Clientxccdf_org.ssgproject.content_rule_sysconfig_networking_bootproto_ifcfg low

Disable DHCP Client

Rule IDxccdf_org.ssgproject.content_rule_sysconfig_networking_bootproto_ifcfg
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 366, Test attestation on 20121024 by DS

Description

For each interface on the system (e.g. eth0), edit /etc/sysconfig/network-scripts/ifcfg-interface and make the following changes:

  • Correct the BOOTPROTO line to read:
    BOOTPROTO=none
  • Add or correct the following lines, substituting the appropriate values based on your site's addressing scheme:
    NETMASK=255.255.255.0
    IPADDR=192.168.1.2
    GATEWAY=192.168.1.1

Rationale

DHCP relies on trusting the local network. If the local network is not trusted, then it should not be used. However, the automatic configuration provided by DHCP is commonly used and the alternative, manual configuration, presents an unacceptable burden in many circumstances.

Enable the NTP Daemonxccdf_org.ssgproject.content_rule_service_chronyd_or_ntpd_enabled medium

Enable the NTP Daemon

Rule IDxccdf_org.ssgproject.content_rule_service_chronyd_or_ntpd_enabled
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AU-8(1), 160, Req-10.4, 3.6, Test attestation on 20121024 by DS

Description

The chronyd service can be enabled with the following command:

$ sudo systemctl enable chronyd.service
Note: The chronyd daemon is enabled by default.

The ntpd service can be enabled with the following command:
$ sudo systemctl enable ntpd.service
Note: The ntpd daemon is not enabled by default. Though as mentioned in the previous sections in certain environments the ntpd daemon might be preferred to be used rather than the chronyd one. Refer to: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/ch-Configuring_NTP_Using_the_chrony_Suite.html for guidance which NTP daemon to choose depending on the environment used.

Rationale

Enabling some of chronyd or ntpd services ensures that the NTP daemon will be running and that the system will synchronize its time to any servers specified. This is important whether the system is configured to be a client (and synchronize only its own clock) or it is also acting as an NTP server to other systems. Synchronizing time is essential for authentication services such as Kerberos, but it is also important for maintaining accurate logs and auditing possible security breaches.

The chronyd and ntpd NTP daemons offer all of the functionality of ntpdate, which is now deprecated. Additional information on this is available at http://support.ntp.org/bin/view/Dev/DeprecatingNtpdate

Specify a Remote NTP Serverxccdf_org.ssgproject.content_rule_chronyd_or_ntpd_specify_remote_server medium

Specify a Remote NTP Server

Rule IDxccdf_org.ssgproject.content_rule_chronyd_or_ntpd_specify_remote_server
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AU-8(1), 160, Req-10.4.1, Req-10.4.3, 3.6, Test attestation on 20121024 by DS

Description

Depending on specific functional requirements of a concrete production environment, the Red Hat Enterprise Linux 7 Server system can be configured to utilize the services of the chronyd NTP daemon (the default), or services of the ntpd NTP daemon. Refer to https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/ch-Configuring_NTP_Using_the_chrony_Suite.html for more detailed comparison of the features of both of the choices, and for further guidance how to choose between the two NTP daemons.
To specify a remote NTP server for time synchronization, perform the following:

  • if the system is configured to use the chronyd as the NTP daemon (the default), edit the file /etc/chrony.conf as follows,
  • if the system is configured to use the ntpd as the NTP daemon, edit the file /etc/ntp.conf as documented below.
Add or correct the following lines, substituting the IP or hostname of a remote NTP server for ntpserver:
server ntpserver
This instructs the NTP software to contact that remote server to obtain time data.

Rationale

Synchronizing with an NTP server makes it possible to collate system logs from multiple sources or correlate computer events with real time events.

Specify Additional Remote NTP Serversxccdf_org.ssgproject.content_rule_chronyd_or_ntpd_specify_multiple_servers low

Specify Additional Remote NTP Servers

Rule IDxccdf_org.ssgproject.content_rule_chronyd_or_ntpd_specify_multiple_servers
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  AU-8(1), Req-10.4.3

Description

Depending on specific functional requirements of a concrete production environment, the Red Hat Enterprise Linux 7 Server system can be configured to utilize the services of the chronyd NTP daemon (the default), or services of the ntpd NTP daemon. Refer to https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System_Administrators_Guide/ch-Configuring_NTP_Using_the_chrony_Suite.html for more detailed comparison of the features of both of the choices, and for further guidance how to choose between the two NTP daemons.
Additional NTP servers can be specified for time synchronization. To do so, perform the following:

  • if the system is configured to use the chronyd as the NTP daemon (the default), edit the file /etc/chrony.conf as follows,
  • if the system is configured to use the ntpd as the NTP daemon, edit the file /etc/ntp.conf as documented below.
Add additional lines of the following form, substituting the IP address or hostname of a remote NTP server for ntpserver:
server ntpserver

Rationale

Specifying additional NTP servers increases the availability of accurate time data, in the event that one of the specified servers becomes unavailable. This is typical for a system acting as an NTP server for other systems.

Disable Postfix Network Listeningxccdf_org.ssgproject.content_rule_postfix_network_listening_disabled medium

Disable Postfix Network Listening

Rule IDxccdf_org.ssgproject.content_rule_postfix_network_listening_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 382, 3.16, Test attestation on 20121024 by DS

Description

Edit the file /etc/postfix/main.cf to ensure that only the following inet_interfaces line appears:

inet_interfaces = localhost

Rationale

This ensures postfix accepts mail messages (such as cron job reports) from the local system only, and not from the network, which protects it from network attack.

Configure SMTP Greeting Bannerxccdf_org.ssgproject.content_rule_postfix_server_banner medium

Configure SMTP Greeting Banner

Rule IDxccdf_org.ssgproject.content_rule_postfix_server_banner
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-22, AU-13

Description

Edit /etc/postfix/main.cf, and add or correct the following line, substituting some other wording for the banner information if you prefer:

smtpd_banner = $myhostname ESMTP

Rationale

The default greeting banner discloses that the listening mail process is Postfix. When remote mail senders connect to the MTA on port 25, they are greeted by an initial banner as part of the SMTP dialogue. This banner is necessary, but it frequently gives away too much information, including the MTA software which is in use, and sometimes also its version number. Remote mail senders do not need this information in order to send mail, so the banner should be changed to reveal only the hostname (which is already known and may be useful) and the word ESMTP, to indicate that the modern SMTP protocol variant is supported.

Enable Postfix Servicexccdf_org.ssgproject.content_rule_service_postfix_enabled low

Enable Postfix Service

Rule IDxccdf_org.ssgproject.content_rule_service_postfix_enabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  Test attestation on 20121024 by DS

Description

The Postfix mail transfer agent is used for local mail delivery within the system. The default configuration only listens for connections to the default SMTP port (port 25) on the loopback interface (127.0.0.1). It is recommended to leave this service enabled for local mail delivery. The postfix service can be enabled with the following command:

$ sudo systemctl enable postfix.service

Rationale

Local mail delivery is essential to some system maintenance and notification tasks.

Uninstall Sendmail Packagexccdf_org.ssgproject.content_rule_package_sendmail_removed medium

Uninstall Sendmail Package

Rule IDxccdf_org.ssgproject.content_rule_package_sendmail_removed
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, Test attestation on 20121024 by DS

Description

Sendmail is not the default mail transfer agent and is not installed by default. The sendmail package can be removed with the following command:

$ sudo yum erase sendmail

Rationale

The sendmail software was not developed with security in mind and its design prevents it from being effectively contained by SELinux. Postfix should be used instead.

Configure LDAP Client to Use TLS For All Transactionsxccdf_org.ssgproject.content_rule_ldap_client_start_tls medium

Configure LDAP Client to Use TLS For All Transactions

Rule IDxccdf_org.ssgproject.content_rule_ldap_client_start_tls
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 776, 778, 1453, Test attestation on 20121024 by DS

Description

Configure LDAP to enforce TLS use. First, edit the file /etc/nslcd.conf, and add or correct the following lines:

ssl start_tls
Then review the LDAP server and ensure TLS has been configured.

Rationale

The ssl directive specifies whether to use ssl or not. If not specified it will default to no. It should be set to start_tls rather than doing LDAP over SSL.

Configure Certificate Directives for LDAP Use of TLSxccdf_org.ssgproject.content_rule_ldap_client_tls_cacertpath medium

Configure Certificate Directives for LDAP Use of TLS

Rule IDxccdf_org.ssgproject.content_rule_ldap_client_tls_cacertpath
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, 776, 778, 1453, Test attestation on 20121024 by DS

Description

Ensure a copy of a trusted CA certificate has been placed in the file /etc/pki/tls/CA/cacert.pem. Configure LDAP to enforce TLS use and to trust certificates signed by that CA. First, edit the file /etc/nslcd.conf, and add or correct either of the following lines:

tls_cacertdir /etc/pki/tls/CA
or
tls_cacertfile /etc/pki/tls/CA/cacert.pem
Then review the LDAP server and ensure TLS has been configured.

Rationale

The tls_cacertdir or tls_cacertfile directives are required when tls_checkpeer is configured (which is the default for openldap versions 2.1 and up). These directives define the path to the trust certificates signed by the site CA.

Uninstall openldap-servers Packagexccdf_org.ssgproject.content_rule_package_openldap-servers_removed low

Uninstall openldap-servers Package

Rule IDxccdf_org.ssgproject.content_rule_package_openldap-servers_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 366, 3.7, Test attestation on 20121024 by DS

Description

The openldap-servers package should be removed if not in use. Is this machine the OpenLDAP server? If not, remove the package.

$ sudo yum erase openldap-servers
The openldap-servers RPM is not installed by default on Red Hat Enterprise Linux 7 machines. It is needed only by the OpenLDAP server, not by the clients which use LDAP for authentication. If the system is not intended for use as an LDAP Server it should be removed.

Rationale

Unnecessary packages should not be installed to decrease the attack surface of the system. While this software is clearly essential on an LDAP server, it is not necessary on typical desktop or workstation systems.

Disable Network File System Lock Service (nfslock)xccdf_org.ssgproject.content_rule_service_nfslock_disabled low

Disable Network File System Lock Service (nfslock)

Rule IDxccdf_org.ssgproject.content_rule_service_nfslock_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.8

Description

The Network File System Lock (nfslock) service starts the required remote procedure call (RPC) processes which allow clients to lock files on the server. If the local machine is not configured to mount NFS filesystems then this service should be disabled. The nfslock service can be disabled with the following command:

$ sudo systemctl disable nfslock.service

Disable Secure RPC Client Service (rpcgssd)xccdf_org.ssgproject.content_rule_service_rpcgssd_disabled low

Disable Secure RPC Client Service (rpcgssd)

Rule IDxccdf_org.ssgproject.content_rule_service_rpcgssd_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.8

Description

The rpcgssd service manages RPCSEC GSS contexts required to secure protocols that use RPC (most often Kerberos and NFS). The rpcgssd service is the client-side of RPCSEC GSS. If the system does not require secure RPC then this service should be disabled. The rpcgssd service can be disabled with the following command:

$ sudo systemctl disable rpcgssd.service

Disable rpcbind Servicexccdf_org.ssgproject.content_rule_service_rpcbind_disabled low

Disable rpcbind Service

Rule IDxccdf_org.ssgproject.content_rule_service_rpcbind_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.8

Description

The rpcbind utility maps RPC services to the ports on which they listen. RPC processes notify rpcbind when they start, registering the ports they are listening on and the RPC program numbers they expect to serve. The rpcbind service redirects the client to the proper port number so it can communicate with the requested service. If the system does not require RPC (such as for NFS servers) then this service should be disabled. The rpcbind service can be disabled with the following command:

$ sudo systemctl disable rpcbind.service

Disable RPC ID Mapping Service (rpcidmapd)xccdf_org.ssgproject.content_rule_service_rpcidmapd_disabled low

Disable RPC ID Mapping Service (rpcidmapd)

Rule IDxccdf_org.ssgproject.content_rule_service_rpcidmapd_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.8

Description

The rpcidmapd service is used to map user names and groups to UID and GID numbers on NFSv4 mounts. If NFS is not in use on the local system then this service should be disabled. The rpcidmapd service can be disabled with the following command:

$ sudo systemctl disable rpcidmapd.service

Configure lockd to use static TCP portxccdf_org.ssgproject.content_rule_nfs_fixed_lockd_tcp_port low

Configure lockd to use static TCP port

Rule IDxccdf_org.ssgproject.content_rule_nfs_fixed_lockd_tcp_port
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Configure the lockd daemon to use a static TCP port as opposed to letting the RPC Bind service dynamically assign a port. Edit the file /etc/sysconfig/nfs. Add or correct the following line:

LOCKD_TCPPORT=lockd-port
Where lockd-port is a port which is not used by any other service on your network.

Rationale

Restrict service to always use a given port, so that firewalling can be done effectively.

Configure lockd to use static UDP portxccdf_org.ssgproject.content_rule_nfs_fixed_lockd_udp_port low

Configure lockd to use static UDP port

Rule IDxccdf_org.ssgproject.content_rule_nfs_fixed_lockd_udp_port
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Configure the lockd daemon to use a static UDP port as opposed to letting the RPC Bind service dynamically assign a port. Edit the file /etc/sysconfig/nfs. Add or correct the following line:

LOCKD_UDPPORT=lockd-port
Where lockd-port is a port which is not used by any other service on your network.

Rationale

Restricting services to always use a given port enables firewalling to be done more effectively.

Configure statd to use static portxccdf_org.ssgproject.content_rule_nfs_fixed_statd_port low

Configure statd to use static port

Rule IDxccdf_org.ssgproject.content_rule_nfs_fixed_statd_port
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Configure the statd daemon to use a static port as opposed to letting the RPC Bind service dynamically assign a port. Edit the file /etc/sysconfig/nfs. Add or correct the following line:

STATD_PORT=statd-port
Where statd-port is a port which is not used by any other service on your network.

Rationale

Restricting services to always use a given port enables firewalling to be done more effectively.

Configure mountd to use static portxccdf_org.ssgproject.content_rule_nfs_fixed_mountd_port low

Configure mountd to use static port

Rule IDxccdf_org.ssgproject.content_rule_nfs_fixed_mountd_port
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Configure the mountd daemon to use a static port as opposed to letting the RPC Bind service dynamically assign a port. Edit the file /etc/sysconfig/nfs. Add or correct the following line:

MOUNTD_PORT=statd-port
Where mountd-port is a port which is not used by any other service on your network.

Rationale

Restricting services to always use a given port enables firewalling to be done more effectively.

Specify UID and GID for Anonymous NFS Connectionsxccdf_org.ssgproject.content_rule_nfs_no_anonymous low

Specify UID and GID for Anonymous NFS Connections

Rule IDxccdf_org.ssgproject.content_rule_nfs_no_anonymous
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

To specify the UID and GID for remote root users, edit the /etc/exports file and add the following for each export:

anonuid=value greater than UID_MAX from /etc/login.defs
anongid=value greater than GID_MAX from /etc/login.defs 
Alternatively, functionally equivalent values of 60001, 65534, 65535 may be used.

Rationale

Specifying the anonymous UID and GID ensures that the remote root user is mapped to a local account which has no permissions on the system.

Disable Network File System (nfs)xccdf_org.ssgproject.content_rule_service_nfs_disabled low

Disable Network File System (nfs)

Rule IDxccdf_org.ssgproject.content_rule_service_nfs_disabled
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  Test attestation on 20121025 by DS

Description

The Network File System (NFS) service allows remote hosts to mount and interact with shared filesystems on the local machine. If the local machine is not designated as a NFS server then this service should be disabled. The nfs service can be disabled with the following command:

$ sudo systemctl disable nfs.service

Rationale

Unnecessary services should be disabled to decrease the attack surface of the system.

Disable Secure RPC Server Service (rpcsvcgssd)xccdf_org.ssgproject.content_rule_service_rpcsvcgssd_disabled low

Disable Secure RPC Server Service (rpcsvcgssd)

Rule IDxccdf_org.ssgproject.content_rule_service_rpcsvcgssd_disabled
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  Test attestation on 20121025 by DS

Description

The rpcsvcgssd service manages RPCSEC GSS contexts required to secure protocols that use RPC (most often Kerberos and NFS). The rpcsvcgssd service is the server-side of RPCSEC GSS. If the system does not require secure RPC then this service should be disabled. The rpcsvcgssd service can be disabled with the following command:

$ sudo systemctl disable rpcsvcgssd.service

Rationale

Unnecessary services should be disabled to decrease the attack surface of the system.

Mount Remote Filesystems with nodevxccdf_org.ssgproject.content_rule_mount_option_nodev_remote_filesystems medium

Mount Remote Filesystems with nodev

Rule IDxccdf_org.ssgproject.content_rule_mount_option_nodev_remote_filesystems
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  CM-7, MP-2, Test attestation on 20121025 by DS

Description

Add the nodev option to the fourth column of /etc/fstab for the line which controls mounting of any NFS mounts.

Rationale

Legitimate device files should only exist in the /dev directory. NFS mounts should not present device files to users.

Mount Remote Filesystems with nosuidxccdf_org.ssgproject.content_rule_mount_option_nosuid_remote_filesystems medium

Mount Remote Filesystems with nosuid

Rule IDxccdf_org.ssgproject.content_rule_mount_option_nosuid_remote_filesystems
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  Test attestation on 20121025 by DS

Description

Add the nosuid option to the fourth column of /etc/fstab for the line which controls mounting of any NFS mounts.

Rationale

NFS mounts should not present suid binaries to users. Only vendor-supplied suid executables should be installed to their default location on the local filesystem.

Mount Remote Filesystems with Kerberos Securityxccdf_org.ssgproject.content_rule_mount_option_krb_sec_remote_filesystems medium

Mount Remote Filesystems with Kerberos Security

Rule IDxccdf_org.ssgproject.content_rule_mount_option_krb_sec_remote_filesystems
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-14(1), 366, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

Add the sec=krb5:krb5i:krb5p option to the fourth column of /etc/fstab for the line which controls mounting of any NFS mounts.

Rationale

When an NFS server is configured to use AUTH_SYS a selected userid and groupid are used to handle requests from the remote user. The userid and groupid could mistakenly or maliciously be set incorrectly. The AUTH_GSS method of authentication uses certificates on the server and client systems to more securely authenticate the remote mount request.

Use Root-Squashing on All Exportsxccdf_org.ssgproject.content_rule_use_root_squashing_all_exports low

Use Root-Squashing on All Exports

Rule IDxccdf_org.ssgproject.content_rule_use_root_squashing_all_exports
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

If a filesystem is exported using root squashing, requests from root on the client are considered to be unprivileged (mapped to a user such as nobody). This provides some mild protection against remote abuse of an NFS server. Root squashing is enabled by default, and should not be disabled.

Ensure that no line in /etc/exports contains the option no_root_squash.

Rationale

If the NFS server allows root access to local file systems from remote hosts, this access could be used to compromise the system.

Evaluation messages
info 
No candidate or applicable check found.
Restrict NFS Clients to Privileged Portsxccdf_org.ssgproject.content_rule_restrict_nfs_clients_to_privileged_ports low

Restrict NFS Clients to Privileged Ports

Rule IDxccdf_org.ssgproject.content_rule_restrict_nfs_clients_to_privileged_ports
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

By default, the server NFS implementation requires that all client requests be made from ports less than 1024. If your organization has control over machines connected to its network, and if NFS requests are prohibited at the border firewall, this offers some protection against malicious requests from unprivileged users. Therefore, the default should not be changed.

To ensure that the default has not been changed, ensure no line in /etc/exports contains the option insecure.

Rationale

Allowing client requests to be made from ports higher than 1024 could allow a unprivileged user to initiate an NFS connection. If the unprivileged user account has been compromised, an attacker could gain access to data on the NFS server.

Ensure Insecure File Locking is Not Allowedxccdf_org.ssgproject.content_rule_no_insecure_locks_exports medium

Ensure Insecure File Locking is Not Allowed

Rule IDxccdf_org.ssgproject.content_rule_no_insecure_locks_exports
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  764

Description

By default the NFS server requires secure file-lock requests, which require credentials from the client in order to lock a file. Most NFS clients send credentials with file lock requests, however, there are a few clients that do not send credentials when requesting a file-lock, allowing the client to only be able to lock world-readable files. To get around this, the insecure_locks option can be used so these clients can access the desired export. This poses a security risk by potentially allowing the client access to data for which it does not have authorization. Remove any instances of the insecure_locks option from the file /etc/exports.

Rationale

Allowing insecure file locking could allow for sensitive data to be viewed or edited by an unauthorized user.

Use Kerberos Security on All Exportsxccdf_org.ssgproject.content_rule_use_kerberos_security_all_exports medium

Use Kerberos Security on All Exports

Rule IDxccdf_org.ssgproject.content_rule_use_kerberos_security_all_exports
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  AC-14(1), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040740

Description

Using Kerberos on all exported mounts prevents a malicious client or user from impersonating a system user. To cryptography authenticate users to the NFS server, add sec=krb5:krb5i:krb5p to each export in /etc/exports.

Rationale

When an NFS server is configured to use AUTH_SYS a selected userid and groupid are used to handle requests from the remote user. The userid and groupid could mistakenly or maliciously be set incorrectly. The AUTH_GSS method of authentication uses certificates on the server and client systems to more securely authenticate the remote mount request.

Disable DNS Serverxccdf_org.ssgproject.content_rule_service_named_disabled low

Disable DNS Server

Rule IDxccdf_org.ssgproject.content_rule_service_named_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 366

Description

The named service can be disabled with the following command:

$ sudo systemctl disable named.service

Rationale

All network services involve some risk of compromise due to implementation flaws and should be disabled if possible.

Uninstall bind Packagexccdf_org.ssgproject.content_rule_package_bind_removed low

Uninstall bind Package

Rule IDxccdf_org.ssgproject.content_rule_package_bind_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 366, 3.9

Description

To remove the bind package, which contains the named service, run the following command:

$ sudo yum erase bind

Rationale

If there is no need to make DNS server software available, removing it provides a safeguard against its activation.

Disable Zone Transfers from the Nameserverxccdf_org.ssgproject.content_rule_dns_server_disable_zone_transfers low

Disable Zone Transfers from the Nameserver

Rule IDxccdf_org.ssgproject.content_rule_dns_server_disable_zone_transfers
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Is it necessary for a secondary nameserver to receive zone data via zone transfer from the primary server? If not, follow the instructions in this section. If so, see the next section for instructions on protecting zone transfers. Add or correct the following directive within /etc/named.conf:

options {
  allow-transfer { none; };
  ...
}

Rationale

If both the primary and secondary nameserver are under your control, or if you have only one nameserver, it may be possible to use an external configuration management mechanism to distribute zone updates. In that case, it is not necessary to allow zone transfers within BIND itself, so they should be disabled to avoid the potential for abuse.

Evaluation messages
info 
No candidate or applicable check found.
Authenticate Zone Transfersxccdf_org.ssgproject.content_rule_dns_server_authenticate_zone_transfers low

Authenticate Zone Transfers

Rule IDxccdf_org.ssgproject.content_rule_dns_server_authenticate_zone_transfers
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

If it is necessary for a secondary nameserver to receive zone data via zone transfer from the primary server, follow the instructions here. Use dnssec-keygen to create a symmetric key file in the current directory:

$ cd /tmp
$ sudo dnssec-keygen -a HMAC-MD5 -b 128 -n HOST dns.example.com
Kdns.example.com .+aaa +iiiii
This output is the name of a file containing the new key. Read the file to find the base64-encoded key string:
$ sudo cat Kdns.example.com .+NNN +MMMMM .key
dns.example.com IN KEY 512 3 157 base64-key-string
Add the directives to /etc/named.conf on the primary server:
key zone-transfer-key {
  algorithm hmac-md5;
  secret "base64-key-string ";
};
zone "example.com " IN {
  type master;
  allow-transfer { key zone-transfer-key; };
  ...
};
Add the directives below to /etc/named.conf on the secondary nameserver:
key zone-transfer-key {
  algorithm hmac-md5;
  secret "base64-key-string ";
};

server IP-OF-MASTER {
  keys { zone-transfer-key; };
};

zone "example.com " IN {
  type slave;
  masters { IP-OF-MASTER ; };
  ...
};

Rationale

The BIND transaction signature (TSIG) functionality allows primary and secondary nameservers to use a shared secret to verify authorization to perform zone transfers. This method is more secure than using IP-based limiting to restrict nameserver access, since IP addresses can be easily spoofed. However, if you cannot configure TSIG between your servers because, for instance, the secondary nameserver is not under your control and its administrators are unwilling to configure TSIG, you can configure an allow-transfer directive with numerical IP addresses or ACLs as a last resort.

Warnings
warning  The purpose of the dnssec-keygen command is to create the shared secret string base64-key-string. Once this secret has been obtained and inserted into named.conf on the primary and secondary servers, the key files Kdns.example.com .+NNN +MMMMM .key and Kdns.example.com .+NNN +MMMMM .private are no longer needed, and may safely be deleted.
Evaluation messages
info 
No candidate or applicable check found.
Disable Dynamic Updatesxccdf_org.ssgproject.content_rule_dns_server_disable_dynamic_updates low

Disable Dynamic Updates

Rule IDxccdf_org.ssgproject.content_rule_dns_server_disable_dynamic_updates
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Is there a mission-critical reason to enable the risky dynamic update functionality? If not, edit /etc/named.conf. For each zone specification, correct the following directive if necessary:

zone "example.com " IN {
  allow-update { none; };
  ...
};

Rationale

Dynamic updates allow remote servers to add, delete, or modify any entries in your zone file. Therefore, they should be considered highly risky, and disabled unless there is a very good reason for their use. If dynamic updates must be allowed, IP-based ACLs are insufficient protection, since they are easily spoofed. Instead, use TSIG keys (see the previous section for an example), and consider using the update-policy directive to restrict changes to only the precise type of change needed.

Evaluation messages
info 
No candidate or applicable check found.
Disable vsftpd Servicexccdf_org.ssgproject.content_rule_service_vsftpd_disabled low

Disable vsftpd Service

Rule IDxccdf_org.ssgproject.content_rule_service_vsftpd_disabled
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 1436

Description

The vsftpd service can be disabled with the following command:

$ sudo systemctl disable vsftpd.service

Rationale

Running FTP server software provides a network-based avenue of attack, and should be disabled if not needed. Furthermore, the FTP protocol is unencrypted and creates a risk of compromising sensitive information.

Uninstall vsftpd Packagexccdf_org.ssgproject.content_rule_package_vsftpd_removed high

Uninstall vsftpd Package

Rule IDxccdf_org.ssgproject.content_rule_package_vsftpd_removed
Result
pass
Time2016-07-11T14:22:44
Severityhigh
Identifiers and References

identifiers: 

references:  CM-6(b), CM-7, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040490, 3.10

Description

The vsftpd package can be removed with the following command:

$ sudo yum erase vsftpd

Rationale

Removing the vsftpd package decreases the risk of its accidental activation.

Install vsftpd Packagexccdf_org.ssgproject.content_rule_package_vsftpd_installed low

Install vsftpd Package

Rule IDxccdf_org.ssgproject.content_rule_package_vsftpd_installed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

If this machine must operate as an FTP server, install the vsftpd package via the standard channels.

$ sudo yum install vsftpd

Rationale

After Red Hat Enterprise Linux 2.1, Red Hat switched from distributing wu-ftpd with Red Hat Enterprise Linux to distributing vsftpd. For security and for consistency with future Red Hat releases, the use of vsftpd is recommended.

Restrict Access to Anonymous Users if Possiblexccdf_org.ssgproject.content_rule_ftp_restrict_to_anon low

Restrict Access to Anonymous Users if Possible

Rule IDxccdf_org.ssgproject.content_rule_ftp_restrict_to_anon
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, AC-3

Description

Is there a mission-critical reason for users to transfer files to/from their own accounts using FTP, rather than using a secure protocol like SCP/SFTP? If not, edit the vsftpd configuration file. Add or correct the following configuration option:

local_enable=NO
If non-anonymous FTP logins are necessary, follow the guidance in the remainder of this section to secure these logins as much as possible.

Rationale

The use of non-anonymous FTP logins is strongly discouraged. Since SSH clients and servers are widely available, and since SSH provides support for a transfer mode which resembles FTP in user interface, there is no good reason to allow password-based FTP access.

Enable Logging of All FTP Transactionsxccdf_org.ssgproject.content_rule_ftp_log_transactions low

Enable Logging of All FTP Transactions

Rule IDxccdf_org.ssgproject.content_rule_ftp_log_transactions
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Add or correct the following configuration options within the vsftpd configuration file, located at /etc/vsftpd/vsftpd.conf:

xferlog_enable=YES
xferlog_std_format=NO
log_ftp_protocol=YES

Rationale

To trace malicious activity facilitated by the FTP service, it must be configured to ensure that all commands sent to the FTP server are logged using the verbose vsftpd log format. The default vsftpd log file is /var/log/vsftpd.log.

Warnings
warning  If verbose logging to vsftpd.log is done, sparse logging of downloads to /var/log/xferlog will not also occur. However, the information about what files were downloaded is included in the information logged to vsftpd.log
Create Warning Banners for All FTP Usersxccdf_org.ssgproject.content_rule_ftp_present_banner medium

Create Warning Banners for All FTP Users

Rule IDxccdf_org.ssgproject.content_rule_ftp_present_banner
Result
notselected
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  48

Description

Edit the vsftpd configuration file, which resides at /etc/vsftpd/vsftpd.conf by default. Add or correct the following configuration options:

banner_file=/etc/issue

Rationale

This setting will cause the system greeting banner to be used for FTP connections as well.

Disable FTP Uploads if Possiblexccdf_org.ssgproject.content_rule_ftp_disable_uploads low

Disable FTP Uploads if Possible

Rule IDxccdf_org.ssgproject.content_rule_ftp_disable_uploads
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Is there a mission-critical reason for users to upload files via FTP? If not, edit the vsftpd configuration file to add or correct the following configuration options:

write_enable=NO
If FTP uploads are necessary, follow the guidance in the remainder of this section to secure these transactions as much as possible.

Rationale

Anonymous FTP can be a convenient way to make files available for universal download. However, it is less common to have a need to allow unauthenticated users to place files on the FTP server. If this must be done, it is necessary to ensure that files cannot be uploaded and downloaded from the same directory.

Place the FTP Home Directory on its Own Partitionxccdf_org.ssgproject.content_rule_ftp_home_partition low

Place the FTP Home Directory on its Own Partition

Rule IDxccdf_org.ssgproject.content_rule_ftp_home_partition
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

By default, the anonymous FTP root is the home directory of the FTP user account. The df command can be used to verify that this directory is on its own partition.

Rationale

If there is a mission-critical reason for anonymous users to upload files, precautions must be taken to prevent these users from filling a disk used by other services.

Disable httpd Servicexccdf_org.ssgproject.content_rule_service_httpd_disabled low

Disable httpd Service

Rule IDxccdf_org.ssgproject.content_rule_service_httpd_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

The httpd service can be disabled with the following command:

$ sudo systemctl disable httpd.service

Rationale

Running web server software provides a network-based avenue of attack, and should be disabled if not needed.

Uninstall httpd Packagexccdf_org.ssgproject.content_rule_package_httpd_removed low

Uninstall httpd Package

Rule IDxccdf_org.ssgproject.content_rule_package_httpd_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7, 3.11

Description

The httpd package can be removed with the following command:

$ sudo yum erase httpd

Rationale

If there is no need to make the web server software available, removing it provides a safeguard against its activation.

Set httpd ServerTokens Directive to Prodxccdf_org.ssgproject.content_rule_httpd_servertokens_prod low

Set httpd ServerTokens Directive to Prod

Rule IDxccdf_org.ssgproject.content_rule_httpd_servertokens_prod
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

ServerTokens Prod restricts information in page headers, returning only the word "Apache."

Add or correct the following directive in /etc/httpd/conf/httpd.conf:

ServerTokens Prod

Rationale

Information disclosed to clients about the configuration of the web server and system could be used to plan an attack on the given system. This information disclosure should be restricted to a minimum.

Evaluation messages
info 
No candidate or applicable check found.
Set httpd ServerSignature Directive to Offxccdf_org.ssgproject.content_rule_httpd_serversignature_off low

Set httpd ServerSignature Directive to Off

Rule IDxccdf_org.ssgproject.content_rule_httpd_serversignature_off
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

ServerSignature Off restricts httpd from displaying server version number on error pages.

Add or correct the following directive in /etc/httpd/conf/httpd.conf:

ServerSignature Off

Rationale

Information disclosed to clients about the configuration of the web server and system could be used to plan an attack on the given system. This information disclosure should be restricted to a minimum.

Evaluation messages
info 
No candidate or applicable check found.
Disable HTTP Digest Authenticationxccdf_org.ssgproject.content_rule_httpd_digest_authentication low

Disable HTTP Digest Authentication

Rule IDxccdf_org.ssgproject.content_rule_httpd_digest_authentication
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The auth_digest module provides encrypted authentication sessions. If this functionality is unnecessary, comment out the related module:

#LoadModule auth_digest_module modules/mod_auth_digest.so

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable HTTP mod_rewritexccdf_org.ssgproject.content_rule_httpd_mod_rewrite low

Disable HTTP mod_rewrite

Rule IDxccdf_org.ssgproject.content_rule_httpd_mod_rewrite
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The mod_rewrite module is very powerful and can protect against certain classes of web attacks. However, it is also very complex and has a significant history of vulnerabilities itself. If its functionality is unnecessary, comment out the related module:

#LoadModule rewrite_module modules/mod_rewrite.so

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable LDAP Supportxccdf_org.ssgproject.content_rule_httpd_ldap_support low

Disable LDAP Support

Rule IDxccdf_org.ssgproject.content_rule_httpd_ldap_support
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The ldap module provides HTTP authentication via an LDAP directory. If its functionality is unnecessary, comment out the related modules:

#LoadModule ldap_module modules/mod_ldap.so
#LoadModule authnz_ldap_module modules/mod_authnz_ldap.so
If LDAP is to be used, SSL encryption should be used as well.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Disable Server Side Includesxccdf_org.ssgproject.content_rule_httpd_server_side_includes low

Disable Server Side Includes

Rule IDxccdf_org.ssgproject.content_rule_httpd_server_side_includes
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Server Side Includes provide a method of dynamically generating web pages through the insertion of server-side code. However, the technology is also deprecated and introduces significant security concerns. If this functionality is unnecessary, comment out the related module:

#LoadModule include_module modules/mod_include.so
If there is a critical need for Server Side Includes, they should be enabled with the option IncludesNoExec to prevent arbitrary code execution. Additionally, user supplied data should be encoded to prevent cross-site scripting vulnerabilities.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable MIME Magicxccdf_org.ssgproject.content_rule_httpd_mime_magic low

Disable MIME Magic

Rule IDxccdf_org.ssgproject.content_rule_httpd_mime_magic
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The mime_magic module provides a second layer of MIME support that in most configurations is likely extraneous. If its functionality is unnecessary, comment out the related module:

#LoadModule mime_magic_module modules/mod_mime_magic.so

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable WebDAV (Distributed Authoring and Versioning)xccdf_org.ssgproject.content_rule_httpd_webdav low

Disable WebDAV (Distributed Authoring and Versioning)

Rule IDxccdf_org.ssgproject.content_rule_httpd_webdav
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

WebDAV is an extension of the HTTP protocol that provides distributed and collaborative access to web content. If its functionality is unnecessary, comment out the related modules:

#LoadModule dav_module modules/mod_dav.so
#LoadModule dav_fs_module modules/mod_dav_fs.so
If there is a critical need for WebDAV, extra care should be taken in its configuration. Since DAV access allows remote clients to manipulate server files, any location on the server that is DAV enabled should be protected by access controls.

Rationale

Minimizing the number of loadable modules available to the web server, reduces risk by limiting the capabilities allowed by the web server.

Disable Server Activity Statusxccdf_org.ssgproject.content_rule_httpd_server_activity_status low

Disable Server Activity Status

Rule IDxccdf_org.ssgproject.content_rule_httpd_server_activity_status
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The status module provides real-time access to statistics on the internal operation of the web server. This may constitute an unnecessary information leak and should be disabled unless necessary. To do so, comment out the related module:

#LoadModule status_module modules/mod_status.so
If there is a critical need for this module, ensure that access to the status page is properly restricted to a limited set of hosts in the status handler configuration.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable Web Server Configuration Displayxccdf_org.ssgproject.content_rule_httpd_server_configuration_display low

Disable Web Server Configuration Display

Rule IDxccdf_org.ssgproject.content_rule_httpd_server_configuration_display
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The info module creates a web page illustrating the configuration of the web server. This can create an unnecessary security leak and should be disabled. If its functionality is unnecessary, comment out the module:

#LoadModule info_module modules/mod_info.so
If there is a critical need for this module, use the Location directive to provide an access control list to restrict access to the information.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable URL Correction on Misspelled Entriesxccdf_org.ssgproject.content_rule_httpd_url_correction low

Disable URL Correction on Misspelled Entries

Rule IDxccdf_org.ssgproject.content_rule_httpd_url_correction
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The speling module attempts to find a document match by allowing one misspelling in an otherwise failed request. If this functionality is unnecessary, comment out the module:

#LoadModule speling_module modules/mod_speling.so
This functionality weakens server security by making site enumeration easier.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable Proxy Supportxccdf_org.ssgproject.content_rule_httpd_proxy_support low

Disable Proxy Support

Rule IDxccdf_org.ssgproject.content_rule_httpd_proxy_support
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The proxy module provides proxying support, allowing httpd to forward requests and serve as a gateway for other servers. If its functionality is unnecessary, comment out the module:

#LoadModule proxy_module modules/mod_proxy.so
If proxy support is needed, load mod_proxy and the appropriate proxy protocol handler module (one of mod_proxy_http, mod_proxy_ftp, or mod_proxy_connect). Additionally, make certain that a server is secure before enabling proxying, as open proxy servers are a security risk. mod_proxy_balancer enables load balancing, but requires that mod status be enabled.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Disable Cache Supportxccdf_org.ssgproject.content_rule_httpd_cache_support low

Disable Cache Support

Rule IDxccdf_org.ssgproject.content_rule_httpd_cache_support
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The cache module allows httpd to cache data, optimizing access to frequently accessed content. However, it introduces potential security flaws such as the possibility of circumventing Allow and Deny directives.

If this functionality is unnecessary, comment out the module:

#LoadModule cache_module modules/mod_cache.so
If caching is required, it should not be enabled for any limited-access content.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Disable CGI Supportxccdf_org.ssgproject.content_rule_httpd_cgi_support low

Disable CGI Support

Rule IDxccdf_org.ssgproject.content_rule_httpd_cgi_support
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The cgi module allows HTML to interact with the CGI web programming language.

If this functionality is unnecessary, comment out the module:

#LoadModule cgi_module modules/mod_cgi.so
If the web server requires the use of CGI, enable mod_cgi.

Rationale

Minimizing the number of loadable modules available to the web server reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Restrict Root Directoryxccdf_org.ssgproject.content_rule_httpd_restrict_root_directory low

Restrict Root Directory

Rule IDxccdf_org.ssgproject.content_rule_httpd_restrict_root_directory
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The httpd root directory should always have the most restrictive configuration enabled.

<Directory / >
   Options None
   AllowOverride None
   Order allow,deny
</Directory>

Rationale

The Web Server's root directory content should be protected from unauthorized access by web clients.

Evaluation messages
info 
No candidate or applicable check found.
Restrict Web Directoryxccdf_org.ssgproject.content_rule_httpd_restrict_web_directory low

Restrict Web Directory

Rule IDxccdf_org.ssgproject.content_rule_httpd_restrict_web_directory
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The default configuration for the web (/var/www/html) Directory allows directory indexing (Indexes) and the following of symbolic links (FollowSymLinks). Neither of these is recommended.

The /var/www/html directory hierarchy should not be viewable via the web, and symlinks should only be followed if the owner of the symlink also owns the linked file.

Ensure that this policy is adhered to by altering the related section of the configuration:

<Directory "/var/www/html">
#  ...
   Options SymLinksIfOwnerMatch
#  ...
</Directory>

Rationale

Access to the web server's directory hierarchy could allow access to unauthorized files by web clients. Following symbolic links could also allow such access.

Evaluation messages
info 
No candidate or applicable check found.
Restrict Other Critical Directoriesxccdf_org.ssgproject.content_rule_httpd_restrict_critical_directories low

Restrict Other Critical Directories

Rule IDxccdf_org.ssgproject.content_rule_httpd_restrict_critical_directories
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

All accessible web directories should be configured with similarly restrictive settings. The Options directive should be limited to necessary functionality and the AllowOverride directive should be used only if needed. The Order and Deny access control tags should be used to deny access by default, allowing access only where necessary.

Rationale

Directories accessible from a web client should be configured with the least amount of access possible in order to avoid unauthorized access to restricted content or server information.

Evaluation messages
info 
No candidate or applicable check found.
Limit Available Methodsxccdf_org.ssgproject.content_rule_httpd_limit_available_methods low

Limit Available Methods

Rule IDxccdf_org.ssgproject.content_rule_httpd_limit_available_methods
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Web server methods are defined in section 9 of RFC 2616 (http://www.ietf.org/rfc/rfc2616.txt). If a web server does not require the implementation of all available methods, they should be disabled.

Note: GET and POST are the most common methods. A majority of the others are limited to the WebDAV protocol.

<Directory /var/www/html>
# ...
   # Only allow specific methods (this command is case-sensitive!)
   <LimitExcept GET POST>
      Order allow,deny
   </LimitExcept>
# ...
</Directory>

Rationale

Minimizing the number of available methods to the web client reduces risk by limiting the capabilities allowed by the web server.

Evaluation messages
info 
No candidate or applicable check found.
Install mod_sslxccdf_org.ssgproject.content_rule_httpd_install_mod_ssl low

Install mod_ssl

Rule IDxccdf_org.ssgproject.content_rule_httpd_install_mod_ssl
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Install the mod_ssl module:

$ sudo yum install mod_ssl

Rationale

mod_ssl provides encryption capabilities for the httpd Web server. Unencrypted content is transmitted in plain text which could be passively monitored and accessed by unauthorized parties.

Evaluation messages
info 
No candidate or applicable check found.
Install mod_securityxccdf_org.ssgproject.content_rule_httpd_install_mod_security low

Install mod_security

Rule IDxccdf_org.ssgproject.content_rule_httpd_install_mod_security
Result
notchecked
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Install the security module:

$ sudo yum install mod_security

Rationale

mod_security provides an additional level of protection for the web server by enabling the administrator to implement content access policies and filters at the application layer.

Evaluation messages
info 
No candidate or applicable check found.
Set Permissions on the /var/log/httpd/ Directoryxccdf_org.ssgproject.content_rule_dir_perms_var_log_httpd low

Set Permissions on the /var/log/httpd/ Directory

Rule IDxccdf_org.ssgproject.content_rule_dir_perms_var_log_httpd
Result
pass
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Ensure that the permissions on the web server log directory is set to 700:

$ sudo chmod 700 /var/log/httpd/
This is its default setting.

Rationale

Access to the web server's log files may allow an unauthorized user or attacker to access information about the web server or alter the server's log files.

Set Permissions on the /etc/httpd/conf/ Directoryxccdf_org.ssgproject.content_rule_dir_perms_etc_httpd_conf low

Set Permissions on the /etc/httpd/conf/ Directory

Rule IDxccdf_org.ssgproject.content_rule_dir_perms_etc_httpd_conf
Result
fail
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Set permissions on the web server configuration directory to 750:

$ sudo chmod 750 /etc/httpd/conf/

Rationale

Access to the web server's configuration files may allow an unauthorized user or attacker to access information about the web server or alter the server's configuration files.

Set Permissions on All Configuration Files Inside /etc/httpd/conf/xccdf_org.ssgproject.content_rule_file_permissions_httpd_server_conf_files low

Set Permissions on All Configuration Files Inside /etc/httpd/conf/

Rule IDxccdf_org.ssgproject.content_rule_file_permissions_httpd_server_conf_files
Result
fail
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  CM-7

Description

Set permissions on the web server configuration files to 640:

$ sudo chmod 640 /etc/httpd/conf/*

Rationale

Access to the web server's configuration files may allow an unauthorized user or attacker to access information about the web server or to alter the server's configuration files.

Disable Dovecot Servicexccdf_org.ssgproject.content_rule_service_dovecot_disabled low

Disable Dovecot Service

Rule IDxccdf_org.ssgproject.content_rule_service_dovecot_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The dovecot service can be disabled with the following command:

$ sudo systemctl disable dovecot.service

Rationale

Running an IMAP or POP3 server provides a network-based avenue of attack, and should be disabled if not needed.

Uninstall dovecot Packagexccdf_org.ssgproject.content_rule_package_dovecot_removed low

Uninstall dovecot Package

Rule IDxccdf_org.ssgproject.content_rule_package_dovecot_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.12

Description

The dovecot package can be uninstalled with the following command:

$ sudo yum erase dovecot

Rationale

If there is no need to make the Dovecot software available, removing it provides a safeguard against its activation.

Enable the SSL flag in /etc/dovecot.confxccdf_org.ssgproject.content_rule_dovecot_enable_ssl low

Enable the SSL flag in /etc/dovecot.conf

Rule IDxccdf_org.ssgproject.content_rule_dovecot_enable_ssl
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

To allow clients to make encrypted connections the ssl flag in Dovecot's configuration file needs to be set to yes.

Edit /etc/dovecot/conf.d/10-ssl.conf and add or correct the following line:

ssl = yes

Rationale

SSL encrypt network traffic between the Dovecot server and its clients protecting user credentials, mail as it is downloaded, and clients may use SSL certificates to authenticate the server, preventing another system from impersonating the server.

Configure Dovecot to Use the SSL Certificate filexccdf_org.ssgproject.content_rule_dovecot_configure_ssl_cert low

Configure Dovecot to Use the SSL Certificate file

Rule IDxccdf_org.ssgproject.content_rule_dovecot_configure_ssl_cert
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

This option tells Dovecot where to find the the mail server's SSL Certificate.

Edit /etc/dovecot/conf.d/10-ssl.conf and add or correct the following line (note: the path below is the default path set by the Dovecot installation. If you are using a different path, ensure you reference the appropriate file):

ssl_cert = </etc/pki/dovecot/certs/dovecot.pem

Rationale

SSL certificates are used by the client to authenticate the identity of the server, as well as to encrypt credentials and message traffic. Not using SSL to encrypt mail server traffic could allow unauthorized access to credentials and mail messages since they are sent in plain text over the network.

Configure Dovecot to Use the SSL Key filexccdf_org.ssgproject.content_rule_dovecot_configure_ssl_key low

Configure Dovecot to Use the SSL Key file

Rule IDxccdf_org.ssgproject.content_rule_dovecot_configure_ssl_key
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

This option tells Dovecot where to find the the mail server's SSL Key.

Edit /etc/dovecot/conf.d/10-ssl.conf and add or correct the following line (note: the path below is the default path set by the Dovecot installation. If you are using a different path, ensure you reference the appropriate file):

ssl_key = </etc/pki/dovecot/private/dovecot.pem

Rationale

SSL certificates are used by the client to authenticate the identity of the server, as well as to encrypt credentials and message traffic. Not using SSL to encrypt mail server traffic could allow unauthorized access to credentials and mail messages since they are sent in plain text over the network.

Disable Plaintext Authenticationxccdf_org.ssgproject.content_rule_dovecot_disable_plaintext_auth low

Disable Plaintext Authentication

Rule IDxccdf_org.ssgproject.content_rule_dovecot_disable_plaintext_auth
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

To prevent Dovecot from attempting plaintext authentication of clients, edit /etc/dovecot/conf.d/10-auth.conf and add or correct the following line:

disable_plaintext_auth = yes

Rationale

Using plain text authentication to the mail server could allow an attacker access to credentials by monitoring network traffic.

Disable Quagga Servicexccdf_org.ssgproject.content_rule_service_zebra_disabled medium

Disable Quagga Service

Rule IDxccdf_org.ssgproject.content_rule_service_zebra_disabled
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  SC-32, 366, SRG-OS-000480-GPOS-00227, RHEL-07-040730

Description

The zebra service can be disabled with the following command:

$ sudo systemctl disable zebra.service

Rationale

Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If routing daemons are used when not required, system network information may be unnecessarily transmitted across the network.

Uninstall quagga Packagexccdf_org.ssgproject.content_rule_package_quagga_removed medium

Uninstall quagga Package

Rule IDxccdf_org.ssgproject.content_rule_package_quagga_removed
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

references:  SC-32, 366, SRG-OS-000480-GPOS-00227, RHEL-07-TBD

Description

The quagga package can be removed with the following command:

$ sudo yum erase quagga

Rationale

Routing software is typically used on routers to exchange network topology information with other routers. If routing software is used when not required, system network information may be unnecessarily transmitted across the network.
If there is no need to make the router software available, removing it provides a safeguard against its activation.

Disable Sambaxccdf_org.ssgproject.content_rule_service_smb_disabled low

Disable Samba

Rule IDxccdf_org.ssgproject.content_rule_service_smb_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  1436

Description

The smb service can be disabled with the following command:

$ sudo systemctl disable smb.service

Rationale

Running a Samba server provides a network-based avenue of attack, and should be disabled if not needed.

Uninstall Samba Packagexccdf_org.ssgproject.content_rule_package_samba_removed low

Uninstall Samba Package

Rule IDxccdf_org.ssgproject.content_rule_package_samba_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.13

Description

The samba package can be uninstalled with the following command:

$ sudo yum erase samba

Rationale

If there is no need to make the Samba software available, removing it provides a safeguard against its activation.

Disable Root Access to SMB Sharesxccdf_org.ssgproject.content_rule_smb_server_disable_root low

Disable Root Access to SMB Shares

Rule IDxccdf_org.ssgproject.content_rule_smb_server_disable_root
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Administrators should not use administrator accounts to access Samba file and printer shares. Disable the root user and the wheel administrator group:

[share]
  invalid users = root @wheel
If administrator accounts cannot be disabled, ensure that local machine passwords and Samba service passwords do not match.

Rationale

Typically, administrator access is required when Samba must create user and machine accounts and shares. Domain member servers and standalone servers may not need administrator access at all. If that is the case, add the invalid users parameter to [global] instead.

Require Client SMB Packet Signing, if using smbclientxccdf_org.ssgproject.content_rule_require_smb_client_signing low

Require Client SMB Packet Signing, if using smbclient

Rule IDxccdf_org.ssgproject.content_rule_require_smb_client_signing
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

To require samba clients running smbclient to use packet signing, add the following to the [global] section of the Samba configuration file, /etc/samba/smb.conf:

client signing = mandatory
Requiring samba clients such as smbclient to use packet signing ensures they can only communicate with servers that support packet signing.

Rationale

Packet signing can prevent man-in-the-middle attacks which modify SMB packets in transit.

Require Client SMB Packet Signing, if using mount.cifsxccdf_org.ssgproject.content_rule_mount_option_smb_client_signing low

Require Client SMB Packet Signing, if using mount.cifs

Rule IDxccdf_org.ssgproject.content_rule_mount_option_smb_client_signing
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

Require packet signing of clients who mount Samba shares using the mount.cifs program (e.g., those who specify shares in /etc/fstab). To do so, ensure signing options (either sec=krb5i or sec=ntlmv2i) are used.

See the mount.cifs(8) man page for more information. A Samba client should only communicate with servers who can support SMB packet signing.

Rationale

Packet signing can prevent man-in-the-middle attacks which modify SMB packets in transit.

Disable Squidxccdf_org.ssgproject.content_rule_service_squid_disabled low

Disable Squid

Rule IDxccdf_org.ssgproject.content_rule_service_squid_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The squid service can be disabled with the following command:

$ sudo systemctl disable squid.service

Rationale

Running proxy server software provides a network-based avenue of attack, and should be removed if not needed.

Uninstall squid Packagexccdf_org.ssgproject.content_rule_package_squid_removed low

Uninstall squid Package

Rule IDxccdf_org.ssgproject.content_rule_package_squid_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.14

Description

The squid package can be removed with the following command:

$ sudo yum erase squid

Rationale

If there is no need to make the proxy server software available, removing it provides a safeguard against its activation.

Disable snmpd Servicexccdf_org.ssgproject.content_rule_service_snmpd_disabled low

Disable snmpd Service

Rule IDxccdf_org.ssgproject.content_rule_service_snmpd_disabled
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

Description

The snmpd service can be disabled with the following command:

$ sudo systemctl disable snmpd.service

Rationale

Running SNMP software provides a network-based avenue of attack, and should be disabled if not needed.

Uninstall net-snmp Packagexccdf_org.ssgproject.content_rule_package_net-snmp_removed low

Uninstall net-snmp Package

Rule IDxccdf_org.ssgproject.content_rule_package_net-snmp_removed
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

identifiers: 

references:  3.15

Description

The net-snmp package provides the snmpd service. The net-snmp package can be removed with the following command:

$ sudo yum erase net-snmp

Rationale

If there is no need to run SNMP server software, removing the package provides a safeguard against its activation.

Configure SNMP Service to Use Only SNMPv3 or Newer xccdf_org.ssgproject.content_rule_snmpd_use_newer_protocol medium

Configure SNMP Service to Use Only SNMPv3 or Newer

Rule IDxccdf_org.ssgproject.content_rule_snmpd_use_newer_protocol
Result
pass
Time2016-07-11T14:22:44
Severitymedium
Identifiers and References

identifiers: 

Description

Edit /etc/snmp/snmpd.conf, removing any references to rocommunity, rwcommunity, or com2sec. Upon doing that, restart the SNMP service:

$ sudo service snmpd restart

Rationale

Earlier versions of SNMP are considered insecure, as they potentially allow unauthorized access to detailed system management information.

Ensure Default SNMP Password Is Not Usedxccdf_org.ssgproject.content_rule_snmpd_not_default_password high

Ensure Default SNMP Password Is Not Used

Rule IDxccdf_org.ssgproject.content_rule_snmpd_not_default_password
Result
pass
Time2016-07-11T14:22:44
Severityhigh
Identifiers and References

identifiers: 

references:  IA-5.1(ii), 366, SRG-OS-000480-GPOS-00227, RHEL-07-040580, Test attestation on 20121214 by MAN

Description

Edit /etc/snmp/snmpd.conf, remove or change the default community strings of public and private. Once the default community strings have been changed, restart the SNMP service:

$ sudo service snmpd restart

Rationale

Whether active or not, default simple network management protocol (SNMP) community strings must be changed to maintain security. If the service is running with the default authenticators, then anyone can gather data about the system and the network and use the information to potentially compromise the integrity of the system and network(s).

Product Meets this Requirementxccdf_org.ssgproject.content_rule_met_inherently_generic low

Product Meets this Requirement

Rule IDxccdf_org.ssgproject.content_rule_met_inherently_generic
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  42, 56, 206, 1084, 66, 85, 86, 185, 223, 171, 172, 1694, 770, 804, 162, 163, 164, 345, 346, 1096, 1111, 1291, 386, 156, 186, 1083, 1082, 1090, 804, 1127, 1128, 1129, 1248, 1265, 1314, 1362, 1368, 1310, 1311, 1328, 1399, 1400, 1404, 1405, 1427, 1499, 1632, 1693, 1665, 1674

Description

This requirement is a permanent not a finding. No fix is required.

Rationale

Red Hat Enterprise Linux meets this requirement through design and implementation.

Product Meets this Requirementxccdf_org.ssgproject.content_rule_met_inherently_auditing low

Product Meets this Requirement

Rule IDxccdf_org.ssgproject.content_rule_met_inherently_auditing
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  130, 157, 131, 132, 133, 134, 135, 159, 174

Description

This requirement is a permanent not a finding. No fix is required.

Rationale

The Red Hat Enterprise Linux audit system meets this requirement through design and implementation.

Product Meets this Requirementxccdf_org.ssgproject.content_rule_met_inherently_nonselected low

Product Meets this Requirement

Rule IDxccdf_org.ssgproject.content_rule_met_inherently_nonselected
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  34, 35, 99, 154, 226, 802, 872, 1086, 1087, 1089, 1091, 1424, 1426, 1428, 1209, 1214, 1237, 1269, 1338, 1425, 1670

Description

This requirement is a permanent not a finding. No fix is required.

Rationale

Red Hat Enterprise Linux meets this requirement through design and implementation.

Guidance Does Not Meet this Requirement Due to Impracticality or Scopexccdf_org.ssgproject.content_rule_unmet_nonfinding_nonselected_scope low

Guidance Does Not Meet this Requirement Due to Impracticality or Scope

Rule IDxccdf_org.ssgproject.content_rule_unmet_nonfinding_nonselected_scope
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  21, 25, 28, 29, 30, 165, 221, 354, 553, 779, 780, 781, 1009, 1094, 1123, 1124, 1125, 1132, 1135, 1140, 1141, 1142, 1143, 1145, 1147, 1148, 1166, 1339, 1340, 1341, 1350, 1356, 1373, 1374, 1383, 1391, 1392, 1395, 1662

Description

This requirement is NA. No fix is required.

Rationale

The guidance does not meet this requirement. The requirement is impractical or out of scope.

Implementation of the Requirement is Not Supportedxccdf_org.ssgproject.content_rule_unmet_finding_nonselected low

Implementation of the Requirement is Not Supported

Rule IDxccdf_org.ssgproject.content_rule_unmet_finding_nonselected
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  20, 31, 52, 144, 1158, 1294, 1295, 1500

Description

This requirement is a permanent finding and cannot be fixed. An appropriate mitigation for the system must be implemented but this finding cannot be considered fixed.

Rationale

RHEL7 does not support this requirement.

Guidance Does Not Meet this Requirement Due to Impracticality or Scopexccdf_org.ssgproject.content_rule_unmet_nonfinding_scope low

Guidance Does Not Meet this Requirement Due to Impracticality or Scope

Rule IDxccdf_org.ssgproject.content_rule_unmet_nonfinding_scope
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  15, 27, 218, 219, 371, 372, 535, 537, 539, 1682, 370, 37, 24, 1112, 1126, 1143, 1149, 1157, 1159, 1210, 1211, 1274, 1372, 1376, 1377, 1352, 1401, 1555, 1556, 1150

Description

This requirement is NA. No fix is required.

Rationale

The guidance does not meet this requirement. The requirement is impractical or out of scope.

A process for prompt installation of OS updates must exist.xccdf_org.ssgproject.content_rule_update_process low

A process for prompt installation of OS updates must exist.

Rule IDxccdf_org.ssgproject.content_rule_update_process
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  1232

Description

Procedures to promptly apply software updates must be established and executed. The Red Hat operating system provides support for automating such a process, by running the yum program through a cron job or by managing the system and its packages through the Red Hat Network or a Satellite Server.

Rationale

This is a manual inquiry about update procedure.

Procedural Requirementxccdf_org.ssgproject.content_rule_c2s_procedural_requirement low

Procedural Requirement

Rule IDxccdf_org.ssgproject.content_rule_c2s_procedural_requirement
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  https://benchmarks.cisecurity.org/tools2/linux/CIS_Red_Hat_Enterprise_Linux_7_Benchmark_v1.1.0.pdf

Description

This requirement is procedural, and can not be met through automated means.

Rationale

This requirement is procedural, and can not be met through automated means.

Not Applicable to Operating Systemxccdf_org.ssgproject.content_rule_c2s_not_OS_applicable low

Not Applicable to Operating System

Rule IDxccdf_org.ssgproject.content_rule_c2s_not_OS_applicable
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  https://benchmarks.cisecurity.org/tools2/linux/CIS_Red_Hat_Enterprise_Linux_7_Benchmark_v1.1.0.pdf

Description

While this requirement is applicable at an information system level, implementation is not performed within the Operating System.

Rationale

This requirement is not applicable to an operating system.

Product Meets this Requirementxccdf_org.ssgproject.content_rule_c2s_met_inherently low

Product Meets this Requirement

Rule IDxccdf_org.ssgproject.content_rule_c2s_met_inherently
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  https://benchmarks.cisecurity.org/tools2/linux/CIS_Red_Hat_Enterprise_Linux_7_Benchmark_v1.1.0.pdf

Description

This requirement is permanent not a finding. No fix is required.

Rationale

Red Hat Enterprise Linux meets this requirement through design and implementation.

Requirement Applies to All Rulesxccdf_org.ssgproject.content_rule_apply_to_everything low

Requirement Applies to All Rules

Rule IDxccdf_org.ssgproject.content_rule_apply_to_everything
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  https://benchmarks.cisecurity.org/tools2/linux/CIS_Red_Hat_Enterprise_Linux_7_Benchmark_v1.1.0.pdf

Description

These are generic requirements, and apply to all rules

Rationale

The following requirements apply to all rules

Rule Compliance through Removal of xinetdxccdf_org.ssgproject.content_rule_cis_xinetd low

Rule Compliance through Removal of xinetd

Rule IDxccdf_org.ssgproject.content_rule_cis_xinetd
Result
notselected
Time2016-07-11T14:22:44
Severitylow
Identifiers and References

references:  2.1.12, 2.1.13, 2.1.14, 2.1.15, 2.1.16, 2.1.17, 2.1.18

Description

The upstream CIS guidance is incorrect, stating that xinetd services can be managed through systemctl. The proper way to disable xinetd services, such as chargen-dgram, is to create a /etc/xinetd.d/SERVICE file which disables the service. Regardless, these rules are inherently compliant with C2S/CIS policies through the removal of xinetd itself.

Rationale

These rules are inherently compliant when xinetd is removed from the system

Red Hat and Red Hat Enterprise Linux are either registered trademarks or trademarks of Red Hat, Inc. in the United States and other countries. All other names are registered trademarks or trademarks of their respective companies.