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.
iDefense reported two integer overflow flaws in the way the X.org server processed CID font files. A malicious authorized client could exploit this issue to cause a denial of service (crash) or potentially execute arbitrary code with root privileges on the X.org server. (CVE-2006-3739, CVE-2006-3740)
Users of X.org should upgrade to these updated packages, which contain a backported patch and is not vulnerable to this issue.