USN-571-2: X.org regression

19 January 2008

xorg-server regression

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 7.10
  • Ubuntu 7.04
  • Ubuntu 6.10
  • Ubuntu 6.06 LTS

Software Description

  • xorg-server

Details

USN-571-1 fixed vulnerabilities in X.org. The upstream fixes were incomplete, and under certain situations, applications using the MIT-SHM extension (e.g. Java, wxWidgets) would crash with BadAlloc X errors. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Multiple overflows were discovered in the XFree86-Misc, XInput-Misc, TOG-CUP, EVI, and MIT-SHM extensions which did not correctly validate function arguments. An authenticated attacker could send specially crafted requests and gain root privileges. (CVE-2007-5760, CVE-2007-6427, CVE-2007-6428, CVE-2007-6429)

It was discovered that the X.org server did not use user privileges when attempting to open security policy files. Local attackers could exploit this to probe for files in directories they would not normally be able to access. (CVE-2007-5958)

It was discovered that the PCF font handling code did not correctly validate the size of fonts. An authenticated attacker could load a specially crafted font and gain additional privileges. (CVE-2008-0006)

Update instructions

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

Ubuntu 7.10
xserver-xorg-core - 2:1.3.0.0.dfsg-12ubuntu8.3
Ubuntu 7.04
xserver-xorg-core - 2:1.2.0-3ubuntu8.3
Ubuntu 6.10
xserver-xorg-core - 1:1.1.1-0ubuntu12.5
Ubuntu 6.06 LTS
xserver-xorg-core - 1:1.0.2-0ubuntu10.10

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system upgrade you need to restart your session to effect the necessary changes.

References