Vulnerability Issue within The Unreal Engine

[Lee @ SCAN]

Thought I'd pass this information to you lot so you can get patching to fix this flaw

Application: Unreal Engine
http://unreal.epicgames.com
Vulnerable games:
- DeusEx <= 1.112fm
- Devastation <= 390
- Mobile Forces <= 20000
- Nerf Arena Blast <= 1.2
- Postal 2 <= 1337
- Rune <= 107
- Tactical Ops <= 3.4.0
- TNN Pro Hunter (?)
- Unreal 1 <= 226f
- Unreal II XMP <= 7710
- Unreal Tournament <= 451b
- Unreal Tournament 2003 <= 2225
- Unreal Tournament 2004 < 3236
- Wheel of Time <= 333b
- X-com Enforcer
NOT vulnerables:
- America's Army
- Dead man's hand
- Magic Battlegrounds
- Rainbow Six: Raven Shield
- Splinter Cell: Pandora tomorrow
- Star Trek: Klingon Honor Guard
- Unreal Tournament 2004 >= 3236
- XIII
Platforms: Windows, Linux and MacOS
Bug: memory overwriting with possible code execution
Risk: critical
Exploitation: remote, versus servers
Date: 18 June 2004
Author: Luigi Auriemma
e-mail: aluigi@altervista.org
web: http://aluigi.altervista.org


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


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


The Unreal engine is the famous game engine developed by EpicGames and
currently is the most used in the videogames world.
Who doesn't know the great Unreal series???


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


Almost all the games based on the Unreal engine support the "secure"
query.
This type of query is part of the so called Gamespy query protocol and
is used to know if the game server is able to calculate an exact
response using a provided string:
http://unreal.epicgames.com/IpServer.htm
http://aluigi.altervista.org/papers/gsmsalg.h

The query is a simple UDP packet like \secure\ABCDEF
If an attacker uses a long value in his secure query, in the Unreal
based game server will be overwritten some important memory zones.

Both remote code execution and spoofing are possibles.


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


The bug has been noticed to EpicGames the 24 May 2004.
Currently only UnrealTournament 2004 has been fixed with the recent
3236 patch.
Check the homepages of the other vulnerable games for possible future
fixes.

However fixing the problem should be enough simple, at least for who
has experience with the UnrealScript language.
In fact the instructions that manage the \secure\ query and pass its
value to the bugged function are written in UnrealScript code and are
located in the files IpDrv.u or IpServerver.u (they depend by the used
engine version).

So happy patching guys - if theres ever a good excuse to keep your games up to date then this is it

[killgORE]

Thanks for that. Duly noted.

One thing though...

That nerf game.. Is that not that DIRE looking kids simulation of quake !

What a pointless game. I am surprised to see it used the fine unreal engine because it looked so crap.