Win32/teerac.gen

I've no idea why F-secure didn't block this, as it does appear to be a severe ransomeware threat.  I assume your machine is now free of the infection, so there's no point suggesting that you Submit a Sample of the file, but maybe if you still have a URL which you think might have been the route to the infection, you could submit that so the Labs can look at it?

I did some Googling, and it seems this even slipped past Malwarebytes Anti-Malware, but they do have a new project in beta, which may be worth looking into.  I've not tried this myself yet, but intend to do so:

https://forums.malwarebytes.org/topic/177751-introducing-malwarebytes-anti-ransomware-beta/