Decade-Old Steam Server Leak Exposes 13TB of Unreleased Valve Prototypes

Game Developer · 2d ago

A publicly reachable legacy Steam endpoint let archivists pull roughly 13 terabytes of internal build data spanning 2003 to 2013, including early prototypes tied to Half-Life 2: Episode 3, Portal 2, and Left 4 Dead 2. Reporting indicates the exposure traces back to old "Steam2" infrastructure that was left accessible rather than a targeted hack of Valve's systems. Dubbed the "Steam2 Teraleak," it is being called one of the largest video-game data exposures on record as archivists sift the trove for playable prototypes.