Please Install the Updated Packages.
X.Org is an open source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon. An integer overflow, which led to a heap-based buffer overflow, was found in the way X.Org server handled trapezoids. A malicious, authorized client could use this flaw to crash the X.Org server or, potentially, execute arbitrary code with root privileges. (CVE-2013-6424) All xorg-x11-server users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue.
xorg-x11-server-common on CentOS 6
Updated on 2015-03-25