Secunia Security Advisory – Some security issues have been reported in X.Org X11, which can be exploited by malicious, local users to perform certain actions with escalated privileges.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/49538/sa21650.txt
Source: https://packetstormsecurity.com/files/49538/Secunia-Security-Advisory-21650.html