On March 28, in a security notice Canonical published details about a libxml2 vulnerability for its Ubuntu 12.10, Ubuntu 12.04 LTS, Ubuntu 11.10, Ubuntu 10.04 LTS, and Ubuntu 8.04 LTS operating systems.
According to Canonical, libxml2 could be made to hang if it received specially crafted input.
It was discovered that libxml2 incorrectly handled XML entity expansion. An attacker could use this flaw to cause libxml2 to consume large amounts of resources, resulting in a denial of service.
The security flaws can be fixed if you upgrade your system(s) to the latest libgoa-1.0-0 and gnome-online-accounts packages, specific to each distribution. To apply the update, run the Update Manager application.
In general, a standard system update will make all the necessary changes. After the system update, you need to reboot your computer to make all the necessary changes.