I'm using ESET SMART SECURITY and I've never had any problems with any of the game's files. I've been playing for 1 year now, so I guess that means it's safe
But if you're still worried, I think there are some online tools that can scan suspect files for you. So it might be worthwhile to do that, just to reassure yourself. But I think you're getting a false positive from your anti virus (still, you're smart to be cautious).