Moderate: libvirt security and bug fix update

Updated libvirt packages that fix one security issue and one bug are now
available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate
security impact. A Common Vulnerability Scoring System (CVSS) base score,
which gives a detailed severity rating, is available from the CVE link in
the References section.

The libvirt library is a C API for managing and interacting with the
virtualization capabilities of Linux and other operating systems. In
addition, libvirt provides tools for remotely managing virtualized systems.

A flaw was found in the way libvirtd handled error reporting for concurrent
connections. A remote attacker able to establish read-only connections to
libvirtd on a server could use this flaw to crash libvirtd. (CVE-2011-1486)

This update also fixes the following bug:

* Previously, running qemu under a different UID prevented it from
accessing files with mode 0660 permissions that were owned by a different
user, but by a group that qemu was a member of. (BZ#668692)

All libvirt users are advised to upgrade to these updated packages, which
contain backported patches to resolve these issues. After installing the
updated packages, libvirtd must be restarted ("service libvirtd restart")
for this update to take effect.

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/kb/docs/DOC-11259

668692 - qemu process is spawned with no supplementary groups
693391 - CVE-2011-1486 libvirt: error reporting in libvirtd is not thread safe

https://www.redhat.com/security/data/cve/CVE-2011-1486.html
https://access.redhat.com/security/updates/classification/#moderate