Solution
Please Install the Updated Packages.
Insight
It was discovered that Libav incorrectly handled certain malformed media files. If a user were tricked into opening a crafted media file, an attacker could cause a denial of service via application crash, or possibly execute arbitrary code with the privileges of the user invoking the program.
Affected
libav on Ubuntu 13.10 ,
Ubuntu 12.10 ,
Ubuntu 12.04 LTS