USN-1990-1: X.Org X server vulnerabilities

Releases

• Ubuntu 13.04
• Ubuntu 12.10
• Ubuntu 12.04

Packages

• xorg-server - X.Org X11 server
• xorg-server-lts-quantal - X.Org X11 server
• xorg-server-lts-raring - X.Org X11 server

Details

Pedro Ribeiro discovered that the X.Org X server incorrectly handled
memory operations when handling ImageText requests. An attacker could use
this issue to cause X.Org to crash, or to possibly execute arbitrary code.
(CVE-2013-4396)

It was discovered that non-root X.Org X servers such as Xephyr incorrectly
used cached xkb files. A local attacker could use this flaw to cause a xkb
cache file to be loaded by another user, resulting in a denial of service.
(CVE-2013-1056)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 13.04

• xserver-xorg-core - 2:1.13.3-0ubuntu6.2

Ubuntu 12.10

• xserver-xorg-core - 2:1.13.0-0ubuntu6.4

Ubuntu 12.04

• xserver-xorg-core-lts-quantal - 2:1.13.0-0ubuntu6.1~precise4
• xserver-xorg-core - 2:1.11.4-0ubuntu10.14
• xserver-xorg-core-lts-raring - 2:1.13.3-0ubuntu6~precise3

After a standard system update you need to reboot your computer to make
all the necessary changes.

References

• CVE-2013-1056
• CVE-2013-4396