####################################################################### Luigi Auriemma Application: Call of Duty 4: Modern Warfare http://www.callofduty.com Versions: <= 1.5 Platforms: Windows (tested) and Linux Bug: Denial of Service Exploitation: remote, versus server (in-game) Date: 02 May 2008 Thanx to: Chronos for the additional tests Author: Luigi Auriemma e-mail: aluigi@autistici.org web: aluigi.org ####################################################################### 1) Introduction 2) Bug 3) The Code 4) Fix ####################################################################### =============== 1) Introduction =============== Call of Duty 4 (CoD4) is the most recent and played game of the homonym series created by Infinity Ward (http://www.infinityward.com) with over 15000 internet servers. ####################################################################### ====== 2) Bug ====== In CoD4 has been introduced a new type of connectionless command (like getinfo, getstatus, connect and so on) called "stats" that seems related to player statistics and can be of 6 types which are sent by the client in sequential order just after having joined the remote game. Exists an additional type (7) which is accepted by the server and if a client uses it the remote server will crash due to a memcpy() with a negative size value (the attacker has no control over the source data and this value). The stats packet requires that the client is in the server since the qport value specified in it and both IP and port must match those used by the player, so the attacker must know the password if the server is protected, being not banned and moreover having a valid cdkey if the internet server requires it. ####################################################################### =========== 3) The Code =========== - plugin for the sudppipe proxy which modifies any stats packet enabling type 7: http://aluigi.org/mytoolz/sudppipe.zip http://aluigi.org/poc/cod4statz_sudp.zip Usage example: sudppipe -l cod4statz_sudp.dll SERVER PORT 20000 then from the CoD4 client type: connect 127.0.0.1:20000 the plugin does a very simple job, when a "stats" packet is received it places the 0x07 byte at offset 12. - stand-alone proof-of-concept which works versus servers without authorization (like LAN servers) for quickly testing the own servers without the need of using a CoD4 client: http://aluigi.org/poc/cod4statz.zip ####################################################################### ====== 4) Fix ====== No fix ####################################################################### --- Luigi Auriemma http://aluigi.org Mobile : Email : Web : http://www.sd.zain.com/ -------------------------------------------------------------------------- -------------------------------------------------------------------------- Disclaimer This communication is intended for the above named person and is confidential and / or legally privileged. Any opinion(s) expressed in this communication are not necessarily those of the Zain. If it has come to you in error you must take no action based upon it, nor must you print it, copy it, forward it, or show it to anyone. Please delete and destroy the e-mail and any attachments and inform the sender immediately. Thank you. Zain is not responsible for the political, religious, racial or partisan opinion in any correspondence conducted by its domain users. Therefore, any such opinion expressed, whether explicitly or implicitly, in any said correspondence is not to be interpreted as that of Zain. Zain may monitor all incoming and outgoing e-mails in line with Zain business practice. Although Zain has taken steps to ensure that e-mails and attachments are free from any virus, we advise that, in keeping with best business practice, the recipient must ensure they are actually virus free. "