USN-1232-3: X.Org X server vulnerability

USN-1232-1 fixed vulnerabilities in the X.Org X server. A regression was
found on Ubuntu 10.04 LTS that affected GLX support, and USN-1232-2 was
released to temporarily disable the problematic security fix. This update
includes a revised fix for CVE-2010-4818.

We apologize for the inconvenience.

Original advisory details:

It was discovered that the X server incorrectly handled certain malformed
input. An authorized attacker could exploit this to cause the X server to
crash, leading to a denial or service, or possibly execute arbitrary code
with root privileges. This issue only affected Ubuntu 10.04 LTS and 10.10.
(CVE-2010-4818)

It was discovered that the X server incorrectly handled certain malformed
input. An authorized attacker could exploit this to cause the X server to
crash, leading to a denial or service, or possibly read arbitrary data from
the X server process. This issue only affected Ubuntu 10.04 LTS.
(CVE-2010-4819)

Vladz discovered that the X server incorrectly handled lock files. A local
attacker could use this flaw to determine if a file existed or not.
(CVE-2011-4028)

Vladz discovered that the X server incorrectly handled setting lock file
permissions. A local attacker could use this flaw to gain read permissions
on arbitrary files and view sensitive information. (CVE-2011-4029)