After a recent spike in interest as old servers were brought back online on Xbox, Call of Duty: Modern Warfare II was taken offline earlier this week on PC over reports of malicious hacks. According to Techcrunch, players were getting attacked in the 2009 game via “hacked lobbies.”
Alerts about malicious activity in the game date back to June 26 with a post on the Steam Discussion page warning that players should make sure they have a virus scanner active before playing. “They attack using hacked lobbies,” wrote Steam user Bee, identifying the malware as “Trojan:Win32 Wacatac.B!ml.” Other players corroborated the issue. “Ye, i just deleted that Trojan,” wrote back Steam user Kordiii. “Was wondering wtf is that.”
According to Techcrunch, hackers were using a worm, a piece of malicious code that can self-replicate and automatically spread from one user to another. Anyone in one of the hacked lobbies would get the virus, and then spread it to whoever they played with next. “This means the hackers must have found and are exploiting one or multiple bugs in the game to execute malicious code on the other players’ computers,” it reported.
Activision ended up taking the Steam version of the game offline on July 26. When asked about the issues, a spokesperson for the company directed Techcrunch to the following tweet: “Multiplayer for Call of Duty: Modern Warfare 2 (2009) on Steam was brought offline while we investigate reports of an issue.”
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Despite being over a decade old, Modern Warfare 2 still averages 500 concurrent players a day on Steam. And that number increased earlier this month after players discovered matchmaking had been improved across a host of older Xbox 360 games. While players on console encountered lag and cheaters, there don’t appear to be any similar reports of malware infections. In the meantime, there’s over a dozen other Call of Duty multiplayer games people can pick up and play.