Scammers Exploit Steam Forums to Distribute Cryptocurrency Mining Scripts

Scammers have launched a campaign on Valve's Steam discussion forums, creating throwaway accounts to reply to users seeking technical help. They persuade victims to run PowerShell with administrator privileges and paste a malicious command. The script installs the XMRig cryptocurrency miner, creates a hidden folder, adds an exception for Microsoft Defender, and schedules the miner to run at every system start. The mining process consumes CPU resources, increases fan noise, and raises electricity costs for the infected computers. The scheme was detailed by security site BleepingComputer, which noted that the fake “Windows optimizer” displays harmless‑looking messages while silently mining Monero.

The attack targets gamers who trust forum advice, leveraging the authority of community members to spread the malicious code without needing to breach the system directly.