14 DAY TRIAL // On April 17, Canonical published details, in a security notice, about an X.Org X server vulnerability for its Ubuntu 12.10, Ubuntu 12.04 LTS, Ubuntu 11.10, and Ubuntu 10.04 LTS operating systems.
According to Canonical, the X server could be made to reveal keystrokes of other users.
It was discovered that the X.Org X server did not properly clear input events in certain circumstances. A local attacker, with physical access, could have used this flaw to capture keystrokes in the operating system.
The security flaws can be fixed if you upgrade your system(s) to the latest xserver-xorg-core and xserver-xorg-core-lts-quantal package, for each specific distribution. To apply the update, run the Update Manager application.
In general, a standard system update will make all the necessary changes. A system restart will be necessary to implement the changes.