Red Hat Security Advisory 2013-1869-01
http://packetstormsecurity.com/files/124528/RHSA-2013-1869-01.txt
Red Hat Security Advisory 2013-1869-01 - Pixman is a pixel manipulation library for the X Window System and Cairo. An integer overflow, which led to a heap-based buffer overflow, was found in the way pixman handled trapezoids. If a remote attacker could trick an application using pixman into rendering a trapezoid shape with specially crafted coordinates, it could cause the application to crash or, possibly, execute arbitrary code with the privileges of the user running the application. Users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue. All applications using pixman must be restarted for this update to take effect.