libvirt 1.0.5.x before 1.0.5.6, 0.10.2.x before 0.10.2.8, and 0.9.12.x before 0.9.12.2 allows local users to bypass intended access restrictions by leveraging a PolkitUnixProcess PolkitSubject race condition in pkcheck via a (1) setuid process or (2) pkexec process, a related issue to CVE-2013-4288.
http://www.ubuntu.com/usn/USN-1954-1
http://www.openwall.com/lists/oss-security/2013/09/18/6
http://wiki.libvirt.org/page/Maintenance_Releases
http://rhn.redhat.com/errata/RHSA-2013-1460.html
http://rhn.redhat.com/errata/RHSA-2013-1272.html
http://lists.opensuse.org/opensuse-updates/2013-10/msg00024.html
http://lists.opensuse.org/opensuse-updates/2013-10/msg00023.html