On June 26, a user on a Steam forum alerted other players of Call of Duty: Modern Warfare 2 that hackers "attack using hacked lobbies," and suggested running an antivirus.

The malware mentioned in the thread appears to be on the malware online repository VirusTotal. Another player claimed to have analyzed the malware and wrote in the same forum thread that the malware appears to be a worm, based on a series of text strings inside the malware.

A game industry insider confirmed that the malware contains those strings, indicating a worm.

Activision spokesperson Neil Wood referred to an  Er posted by the company on an official Call of Duty updates Er account, which vaguely acknowledges the malware.

“Multiplayer for Call of Duty: Modern Warfare 2 on Steam was brought offline while we investigate reports of an issue,” the Er read.

The game has been around since 2009 and is even more out of fashion than shoulder pads.  It has been estimated that there are only 600 players of the game world wide.