Ubuntu Security Notice USN-214-1 – Chris Evans discovered several buffer overflows in the libungif library. By tricking an user (or automated system) into processing a specially crafted GIF image, this could be exploited to execute arbitrary code with the privileges of the application using libungif.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/41393/usn-214-1.txt
Source: https://packetstormsecurity.com/files/41393/usn-214-1.txt.html