On Wed, May 03, 2023 at 02:48:05PM -0500, Carl George wrote:
On Thu, Apr 27, 2023 at 9:42 AM Dave Dykstra via epel-devel
<epel-devel(a)lists.fedoraproject.org> wrote:
>
> We believe that it is important to apply this change to all EPEL releases,
> for these reasons:
> 1. The general vulnerability described in this CVE applies equally to all
> currently supported Linux distributions. The Singularity/Apptainer
CVE-2023-30549 only applies to apptainer on RHEL 7 because the
underlying vulnerability (CVE-2022-1184) has been fixed on RHEL 8 and
9.
CVE-2023-30549 most urgently applies to RHEL 7 because of the example
of CVE-2022-1184, but as I explain in the rest of the point, it also
applies in general to any similar moderate or low severity memory-
corruption ext4 vulnerability that will come in the future on RHEL 8 &
RHEL 9 because Red Hat has no motivation to fix them urgently.
> community has long been aware that making setuid-root
kernel
> filesystem mounts available to all users has been a risk, because
>
https://lwn.net/Articles/652468/ briefly explained that kernel
> developers considered that to be a great risk. System admins have
> been willing to live with the risk because (a) nobody had identified
> an attack, (b) the functionality was so useful, especially the
> squashfs mounts, and (c) there wasn't an alternative. With the new
> information from the ext4 kernel filesystem owner, we now have more
> specifics on how the attack can be done including an example
> vulnerability, the ext3 mounts aren't as widely used as squashfs,
> and Apptainer has an alternative using unprivileged user namespaces.
> 2. RHEL8 & RHEL9 have unprivileged user namespaces enabled by default,
> so the functionality will still be available to most of the users.
> It does not automatically switch to the alternative, but there's a
> clear error message saying that it is disabled by configuration and
> suggesting that users add the --userns option (and of course if
> apptainer-suid is not installed it uses the user namespace mode
> automatically).
> 3. It is important to have consistency across platforms, since users and
> administrators often use more than one and it would be confusing to
> have different behavior on different platforms. Admins can also
If consistency across platforms is important, then it seems prudent to
avoid this incompatible update across all three platforms, especially
this late in the RHEL 7 lifecycle.
It's not prudent to leave RHEL 7 exposed to high-severity vulnerabilities.
Apptainer also supports more platforms than Red Hat.
> install the rpm on RHEL8 & 9 directly from github, and
it would not
> be good to have different behavior when installed from EPEL.
Dave