Steam Support :: Valve Anti-Cheat (VAC) System
help.steampowered.com › en › faqsVAC stands for Valve Anti-Cheat, an automated system designed to detect cheats installed on users' computers. If a user connects to a VAC-Secured server from a computer with identifiable cheats installed, the VAC system will ban the user from playing that game on VAC-Secured servers in the future. The VAC system reliably detects cheats using ...