I'm skeptical that it's actually present, and think that it's a false positive from the other user. A lot of those heuristic malware detection systems get really weirded out by games because a lot of the software techniques games use can look a lot like malware.
For example, what's a common thing malware will do? It will read your keystrokes and try to send that data back to a remote server. What will a game do? It reads keystrokes (for input reasons so you can, you know, play the game) and will check for updates on a remote server. As such, unless a title is whitelisted or they're very careful about what they detect, games will incorrectly trigger a lot of malware detection systems that rely on application behavior tracking.
