Several security issues were fixed in the X.Org X server.
Olivier Fourdan discovered that the X.Org X server incorrectly handled XkbSetGeometry requests resulting in an information leak. An attacker able to connect to an X server, either locally or remotely, could use this issue to possibly obtain sensitive information. (CVE-2015-0255)
17 February 2015
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the X.Org X server.
Olivier Fourdan discovered that the X.Org X server incorrectly handled XkbSetGeometry requests resulting in an information leak. An attacker able to connect to an X server, either locally or remotely, could use this issue to possibly obtain sensitive information. (CVE-2015-0255)
It was discovered that the X.Org X server incorrectly handled certain trapezoids. An attacker able to connect to an X server, either locally or remotely, could use this issue to possibly crash the server. This issue only affected Ubuntu 12.04 LTS. (CVE-2013-6424)
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.
Vulmon