Scientific Linux Security Update : libvirt on SL6.x i386/x86_64

This script is Copyright (C) 2013 Tenable Network Security, Inc.


Synopsis :

The remote Scientific Linux host is missing one or more security
updates.

Description :

It was found that libvirtd leaked file descriptors when listing all
volumes for a particular pool. A remote attacker able to establish a
read- only connection to libvirtd could use this flaw to cause
libvirtd to consume all available file descriptors, preventing other
users from using libvirtd services (such as starting a new guest)
until libvirtd is restarted. (CVE-2013-1962)

This update also fixes the following bugs :

- Previously, libvirt made control group (cgroup) requests
on files that it should not have. With older kernels,
such nonsensical cgroup requests were ignored
however,
newer kernels are stricter, resulting in libvirt logging
spurious warnings and failures to the libvirtd and audit
logs. The audit log failures displayed by the ausearch
tool were similar to the following :

root [date] - failed cgroup allow path rw /dev/kqemu

With this update, libvirt no longer attempts the nonsensical cgroup
actions, leaving only valid attempts in the libvirtd and audit logs
(making it easier to search for real cases of failure).

- Previously, libvirt used the wrong variable when
constructing audit messages. This led to invalid audit
messages, causing ausearch to format certain entries as
having 'path=(null)' instead of the correct path. This
could prevent ausearch from locating events related to
cgroup device ACL modifications for guests managed by
libvirt. With this update, the audit messages are
generated correctly, preventing loss of audit coverage.

After installing the updated packages, libvirtd will be restarted
automatically.

See also :

http://www.nessus.org/u?e36d8b86

Solution :

Update the affected packages.

Risk factor :

Medium / CVSS Base Score : 5.0
(CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P)

Family: Scientific Linux Local Security Checks

Nessus Plugin ID: 66491 ()

Bugtraq ID:

CVE ID: CVE-2013-1962