Valve Advises Users of Malicious Steam Game BlockBlasters to Reinstall Their OS
Valve is warning users who installed and ran the malicious Steam game BlockBlasters to take immediate action. Affected players are advised to scan their systems with antivirus tools and, in severe cases, consider a full operating system reinstallation.
How the Attack Came to Light
The malicious game drew attention earlier this week when streamer Raivo Plavnieks (known as RastalandTV) revealed that he had lost $32,000 in donations for his cancer treatment after installing BlockBlasters.
Further investigation showed the attack was widespread. Blockchain analyst ZachXBT reported that the operators behind the game stole at least $150,000 from 261 Steam users. Researchers at VXUnderground tracked an even higher victim count—478 users.
A Targeted Campaign
Researchers note that victims were not chosen at random. The attackers reportedly identified individuals on X (formerly Twitter) who held significant amounts of cryptocurrency. They then sent direct messages encouraging those users to install and promote BlockBlasters.
The game has since been removed from Steam, though archived versions remain available online.
Valve’s Response
Although Valve has not issued a formal public statement, Reddit users report receiving direct warnings from the company.
According to those messages, BlockBlasters was safe until August 30, 2025. On that date, a malicious cryptocurrency-stealing component was added. Anyone who launched the game after August 30 may have been compromised.
Valve’s warning advises users to:
- Run a full antivirus scan,
- Check for suspicious or recently installed programs, and
- Consider a complete OS reinstallation to ensure the removal of malware.
