USN-341-1: libxfont vulnerability

7 September 2006

libxfont, xorg vulnerability

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

  • Ubuntu 6.06 LTS
  • Ubuntu 5.10
  • Ubuntu 5.04

Software Description


An integer overflow has been discovered in’s font handling library. By using a specially crafted font file, this could be exploited to crash the X server or execute arbitrary code with root privileges.

Update instructions

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

Ubuntu 6.06 LTS
libxfont1 - 1:1.0.0-0ubuntu3.1
Ubuntu 5.10
libxfont1 - 1:0.99.0+cvs.20050909-1.1
Ubuntu 5.04
libfs6 - 6.8.2-10.3
xserver-xorg - 6.8.2-10.3

To update your system, please follow these instructions:

After a standard system upgrade you need to reboot your computer to effect the necessary changes.