Users offered phoney trade offers and supplied with hidden trojan viruses.
Hackers are once again targeting Steam by offering users phoney in-game items through the gaming platform’s Marketplace, according to the security company Malwarebytes.
Attackers were found to be setting up trade offers by sending images through the service’s messaging client, with the pictures turning out to be a trojan files disguised as screensavers (.scr).
Christopher Boyd, malware intelligence analyst at Malwarebytes, said: "Just because the name of the file says "IMG" at the start doesn’t mean it’s actually an image file.
"The extension in these cases is the giveaway, and users of Steam should ensure they’re not being set up for a harsh lesson in digital shenanigans."
Once a hacker has installed the virus they can use it to obtain the session ID of the Steam user, gain access to their inventory and save items onto an "offer list" for selling to other players, according to the firm.
Viruses are also used to send out further message to the victims’ contact list, making the scam seem more plausible to subsequent targets.
"A search for .scr files on the Steam Community forums reveals quite a lot of fresh ‘I opened this .scr file and now I’m having a bad hair day’ posts in the last few days," Boyd added. "So please ensure you avoid any and all links sent via Steam chat which lead to .scr files."