Cheater report on MW3
Player named Vale was using wallhack on a server i'm admin on. Proof is in this demo file. sv_cheats is disabled on the server.
watch how he watches through walls the entire time, and the final kill towards the end pretty much gave it away. i was hiding in a corner with assassin and he was looking at me and a teammate through the wall and started shooting me before i was even visible on screen.