Thanks for the response Steve. That is what I had figured.

But because both the RHEL6 SSG and RHEL6 STIG require this functionality to be configured only in /etc/login.defs as opposed to /etc/pam.d/system-auth, it was questionable.

While system certifications simply require checking that a system is configured in accordance with a published STIG, DSS will actually check to see that the intended requirements are actually enforced (i.e. actually attempt a non-compliant password as opposed to checking for applied settings).

So if we are all in agreement, could the SSG check and fix for this please be changed to include the setting that gets enforced (minlen=14 in /etc/pam.d/system-auth)?


Best regards,

Trey Henefield, CISSP
Senior IAVA Engineer

Ultra Electronics
Advanced Tactical Systems, Inc.
4101 Smith School Road
Building IV, Suite 100
Austin, TX 78744 USA
Tel: +1 512 327 6795 ext. 647
Fax: +1 512 327 8043
Mobile: +1 512 541 6450

-----Original Message-----
From: Steve Grubb []
Sent: Thursday, March 20, 2014 7:59 AM
Cc: Trey Henefield
Subject: Re: Minimum Password Length ...

On Thursday, March 20, 2014 07:28:34 AM Trey Henefield wrote:
> Nobody has seemed to respond to this. But this is an issue.
> In /etc/login.defs, I have PASS_MIN_LEN set to 14, yet as a user, I
> can set the following password 56tyghbn%^TY which only has 12
> characters via the passwd command.

In our common criteria setup, we have annotated the login.defs file with the following:

# The evaluated configuration constraints are:
# PASS_MAX_DAYS MAY be changed, must be <= 60 # PASS_MAX_DAYS MAY be changed, 0 < PASS_MIN_DAYS < PASS_MAX_DAYS # PASS_MIN_LEN has no effect in the evaluated configuration # PASS_WARN_AGE MAY be changed

Note...has no effect...

The intended way can be seen in system-auth:

password requisite try_first_pass retry=3 type=
password sufficient sha512 shadow nullok try_first_pass use_authtok
password required

Of these, cracklib is responsible for enforcing password policy. Checking its man page, it has something called minlen. Looking at the RHEL5 USGCB settings, this is in fact how it's set:

sed -i "/ minlen=12 dcredit=-1 ucredit=-1 ocredit=-1 lcredit=-1 difok=3/" /etc/pam.d/system-auth

So, to have 14, alter the above settings to correct it.


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