Latest update causes avast! to pick up hl2.exe as a Trojan

So after the latest update today avast did a virus check it picked hl2.exe up as a trojan in the GMOD folder, and deleted it. Upon research, apparently some other people have had the same issue. Most antiviruses, including avast! see hl2.exe as a trojan/backdoor and remove it, rendering the game unplayable. I doubt this is something to be worried about, so what should I do to work around this?

Solution: don’t use Avast.

Seriously, MSE is all you’ll ever need unless you download porn via P2P programs or something. You’re even using Windows 8, which has it built in.

There was no update.

The update you see is Steam trying to download hl2.exe after Avast removed it.

Add hl2.exe to exceptions and report it as false positive.