Red Hat Security Advisory 2012-0303-03 - 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. A flaw was found in the way the X.Org server handled lock files. A local user with access to the system console could use this flaw to determine the existence of a file in a directory not accessible to the user, via a symbolic link attack.
39e0f6df5d345b03733218c038d1f55b80c5a015bd9aa8236f5b26bc71730c62