The TIFF library could be made to run programs as your login if it opened a specially crafted file.
It was discovered that the TIFF library incorrectly handled certain JPEG data. If a user or automated system were tricked into opening a specially crafted TIFF image, a remote attacker could execute arbitrary code with user privileges, or crash the application, leading to a denial of service.
21 April 2011
A security issue affects these releases of Ubuntu and its derivatives:
The TIFF library could be made to run programs as your login if it opened a specially crafted file.
It was discovered that the TIFF library incorrectly handled certain JPEG data. If a user or automated system were tricked into opening a specially crafted TIFF image, a remote attacker could execute arbitrary code with user privileges, or crash the application, leading to a denial of service.
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 restart your session to make all the necessary changes.