Several weeks ago I started to get a lot of popups. It happened within a couple of hours of taking Steam out of Startup. I have my virus scan (Avast) set to run everyday at 11 am, but thought maybe I should run it again manually at 4 pm. I did, and sure enough found a virus with Steam mentioned. I immediately took care of it and ran a boot scan, which found 2 trojans.
I should have come here to mention it, but I'm dealing with bad back problems right now and was on meds, not thinking straight.
So, run an extra scan and do a boot scan if you use Steam. The browser I'm using is Firefox.
Checking my log: the files were found in c:\program files\steam bin. That was a Win32 trojan. It also mentions Steamservice.dll. Also an AppOverlay.dll in C:\program files\Steam. That was another Win32Trojan.
Another was filesystem_steam.dll. That one was win32malware.
Hope this helps.
Last edited by JeanK; 10/22/12 11:06 AM. Reason: Added file info