Libav could be made to crash or run programs as your login if it opened a specially crafted file.
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.
11 June 2014
A security issue affects these releases of Ubuntu and its derivatives:
Libav could be made to crash or run programs as your login if it opened a specially crafted file.
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.
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.
This update uses a new upstream release, which includes additional bug fixes. In general, a standard system update will make all the necessary changes.