Gdm (the GNOME Display Manager) is a highly configurable reimplementation of xdm, the X Display Manager. Gdm allows you to log into your system with the X Window System running and supports running several different X sessions on your local machine at the same time.
Marcus Meissner discovered a race condition issue in the way Gdm modifies the permissions on the .ICEauthority file. A local attacker could exploit this flaw to gain privileges. Due to the nature of the flaw, however, a successful exploitation was unlikely. (CVE-2006-1057)
This erratum also includes a bug fix to correct the pam configuration for the audit system.
All users of gdm should upgrade to this updated package, which contains backported patches to resolve these issues.