Valve is sending warnings to users who installed and launched the malicious game BlockBlasters, recently discovered on Steam. Affected users are advised to scan their systems with antivirus software and also consider a complete OS reinstallation.
Earlier this week, a malicious game called BlockBlasters was discovered on Steam. Attention to the issue was drawn by the case of streamer Raivo Plavnieks, known as RastalandTV. He was trying to raise money for treatment of stage-four cancer, but after installing BlockBlasters he lost $32,000 received as donations.
Further investigation showed that hundreds of users were affected by the malicious game. As reported by well-known blockchain analyst ZachXBT, the attackers behind BlockBlasters stole at least $150,000 from 261 Steam users.
Researchers from the VXUnderground team were also tracking this attack. According to their data, there were even more victims — 478 people.
At the same time, the researchers wrote that these users were deliberately selected as targets. The attackers searched the social network X (formerly Twitter) for people with substantial amounts of cryptocurrency, then sent them messages asking them to try the game and promote it.
At present, BlockBlasters has already been removed from Steam (an archived version can be seen here).
Although Valve representatives have not issued official comments on this incident, Reddit users report that the company is sending warnings to potential victims.
In its message, Valve confirms the findings of infosec specialists and says that the game was safe until August 30, 2025, and only after that date a malicious component for stealing cryptocurrency was added to it.
Anyone who ran the game after this date is advised to scan their system with antivirus software, look for suspicious and recently installed programs, and consider a full OS reinstall to ensure no malware remains.