Half-Life Client Server Message Format String Vulnerability



Date Discovered

January 10, 2003


It has been reported that the Half-Life client contains a format string vulnerability. When receiving messages from an administrator through the adminmod add-on package, the client does not properly handle input. This could result in denial of service, or code execution.

Technologies Affected

  • Valvesoftware Half-Life 1.1.0 .0.8
  • Valvesoftware Half-Life 1.1.0 .0.9
  • Valvesoftware Half-Life 1.1.1 .0


Run all software as a nonprivileged user with minimal access rights.
Do not execute Half-Life client software as a privileged user.

Do not use client software to access unknown or untrusted hosts from critical systems.
Do not connect to unknown or untrusted Half-Life clients.

Currently we are not aware of any vendor-supplied patches for this issue. If you feel we are in error or are aware of more recent information, please mail us at: vuldb@securityfocus.com <mailto:vuldb@securityfocus.com>.


Vulnerability discovery credited to "VOID.AT Security" <crew@void.at>.

© 1995- Symantec Corporation

Permission to redistribute this alert electronically is granted as long as it is not edited in any way unless authorized by Symantec Security Response. Reprinting the whole or part of this alert in any medium other than electronically requires permission from secure@symantec.com.


The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.

Symantec, Symantec products, Symantec Security Response, and secure@symantec.com are registered trademarks of Symantec Corp. and/or affiliated companies in the United States and other countries. All other registered and unregistered trademarks represented in this document are the sole property of their respective companies/owners.