Server termination in America's Army 2.8.3.1

[Luigi Auriemma <aluigi () autistici org>]

#######################################################################

                             Luigi Auriemma

Applications: America's Army
              http://www.americasarmy.com
Versions:     <= 2.8.3.1
Platforms:    Windows (tested), Linux and Mac
Bug:          server termination due to failed assertion
Exploitation: remote, versus server
Date:         02 Aug 2008
Author:       Luigi Auriemma
              e-mail: aluigi () autistici org
              web:    aluigi.org


#######################################################################


1) Introduction
2) Bug
3) The Code
4) Fix


#######################################################################

===============
1) Introduction
===============


> From Wikipedia:
"America's Army (also known as AA or Army Game Project) is a tactical
multiplayer first-person shooter owned by the United States Government
and released as a global public relations initiative to help with U.S.
Army recruitment."


#######################################################################

======
2) Bug
======


The AA server can be terminated remotely through a specific single
spoofable UDP packet which leads to a failed assertion:

  "Assertion failed: VoiceIndex<VOICE_MAX_CHATTERS"

Note: this bug is the same I found and disclosed in Unreal Tournament
2004 some days ago and which affects some other games too (ut2004null).


#######################################################################

===========
3) The Code
===========


http://aluigi.org/poc/armynchia.zip


#######################################################################

======
4) Fix
======


No fix


#######################################################################


--- 
Luigi Auriemma
http://aluigi.org
http://backup.aluigi.org
http://mirror.aluigi.org