Several security issues were fixed in libxml2.
It was discovered that libxml2 would load XML external entities by default. If a user or automated system were tricked into opening a specially crafted document, an attacker could possibly obtain access to arbitrary files or cause resource consumption. This issue only affected Ubuntu 10.04 LTS, Ubuntu 12.04 LTS, and Ubuntu 12.10. (CVE-2013-0339)
15 July 2013
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in libxml2.
It was discovered that libxml2 would load XML external entities by default. If a user or automated system were tricked into opening a specially crafted document, an attacker could possibly obtain access to arbitrary files or cause resource consumption. This issue only affected Ubuntu 10.04 LTS, Ubuntu 12.04 LTS, and Ubuntu 12.10. (CVE-2013-0339)
It was discovered that libxml2 incorrectly handled documents that end abruptly. If a user or automated system were tricked into opening a specially crafted document, an attacker could possibly cause libxml2 to crash, resulting in a denial of service. (CVE-2013-2877)
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.