Vulnerability Note VU#203220

X.Org PCF font parser buffer overflow

Original Release date: 19 Mar 2008 | Last revised: 19 Mar 2008


A vulnerability in the X.Org server could allow a remote attacker to execute arbitrary code on an affected system.


The X.Org project provides an open source implementation of the X Window System. The server supports bitmapped fonts in various formats, including Portable Compiled Font (PCF) format. A flaw exists in the handling of PCF fonts where the difference between lastCol and firstCol in the PCF_BDF_ENCODINGS table is greater than 255. An attacker with the ability to cause the X server to open a specially crafted PCF font file could cause a buffer overflow in the X server.


A remote attacker with an established, authenticated connection to the X server could execute arbitrary code with the privileges of the X server or cause the server to crash.


Upgrade or apply a patch from the vendor

Patches and updated versions of the software have been released to address this issue. Please see the Systems Affected section of this document for more information.

Users who compile their X.Org system from the original source distribution should review the X.Org security advisory of January 17th, 2008

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Fedora ProjectAffected-19 Mar 2008
Gentoo LinuxAffected-19 Mar 2008
Mandriva, Inc.Affected-19 Mar 2008
OpenBSDAffected-19 Mar 2008
Red Hat, Inc.Affected-19 Mar 2008
SUSE LinuxAffected-19 Mar 2008
UbuntuAffected-19 Mar 2008 FoundationAffected26 Sep 200705 Mar 2008
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



Thanks to Takuya Shiozaki working through JPCERT/CC for reporting this vulnerability.

This document was written by Chad R Dougherty.

Other Information

  • CVE IDs: CVE-2008-0006
  • Date Public: 17 Jan 2008
  • Date First Published: 19 Mar 2008
  • Date Last Updated: 19 Mar 2008
  • Severity Metric: 11.54
  • Document Revision: 9


If you have feedback, comments, or additional information about this vulnerability, please send us email.