: VAC scans for known patterns (signatures) of loader code. If a loader is "detected," any account using it is typically hit with a permanent ban.
Technical Overview of Counter-Strike: Global Offensive (CS:GO) Hack Loaders CSGO Hack Loader
: To prevent anti-cheat systems from detecting the cheat file on a hard drive, many loaders "stream" the cheat data directly from a remote server into the computer’s RAM. : VAC scans for known patterns (signatures) of loader code