According to security blogger Graham Cluley, Steam chat is being the current source for malware dissemination. How does it “work”, so to speak? A user will be on the receiving end of a message that contains “WTF?????”, where it will be accompanied by a link for the receiver to click on, which looks like an innocent JPEG file. In reality, it carries a .SCR Windows executable file, which holds malicious code which will be used to infiltrate the recipient’s computer.
Basically, if you receive such a message, chances are one of your contacts has been infected – and it would be wise not to click on the link at all. Cluley blogged about it, saying, “The problem of malicious .SCR files spreading across the Steam network is sadly not a new one. For instance, back in September researchers at MalwareBytes warned of the threat.”