Several security issues were fixed in libvirt.
It was discovered that libvirt used the pkcheck tool in an unsafe manner. A local attacker could possibly use this flaw to bypass polkit authentication. In Ubuntu, libvirt polkit authentication is not enabled by default. (CVE-2013-4311)
18 September 2013
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in libvirt.
It was discovered that libvirt used the pkcheck tool in an unsafe manner. A local attacker could possibly use this flaw to bypass polkit authentication. In Ubuntu, libvirt polkit authentication is not enabled by default. (CVE-2013-4311)
It was discovered that libvirt incorrectly handled certain memory stats requests. A remote attacker could use this issue to cause libvirt to crash, resulting in a denial of service. This issue only affected Ubuntu 12.04 LTS, Ubuntu 12.10, and Ubuntu 13.04. (CVE-2013-4296)
It was discovered that libvirt incorrectly handled certain bitmap operations. A remote attacker could use this issue to cause libvirt to crash, resulting in a denial of service. This issue only affected Ubuntu 13.04. (CVE-2013-5651)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.
Vulmon