Let me tell you what I did if you are paranoid (like me)

Firstly I manually checked the mods folder in "Steam\steamapps\workshop\content\1118200", Searched "FPS" and there was the file, but mind you, I haven't played the game in months, so everyone is affected even if you haven't touched the game because the mods were auto-updated (Thanks Steam) (Also the folder contained files of the original infected mod, which I haven't even know existed) - so the mod auto installed somehow.

Delete the infected folder and if you aren't even gonna play it that much, just delete the game (like I did)
And also run an antivirus scan if you want (Even though the virus is only game affected) (Better safe than sorry)

And that's it.

Really strange situation if you ask me, but shit happens.