TerminalFix Uses Fake Cloudflare CAPTCHAs to Deploy Reverse
Microsoft details TerminalFix, a ClickFix variant using fake Cloudflare CAPTCHAs to make users run PowerShell payloads with reverse-tunnel implants.
Microsoft disclosed TerminalFix campaigns that direct users to run commands in Windows Terminal or PowerShell instead of the Run dialog, increasing the chance multi-line scripts execute. Compromised websites serve fake Cloudflare CAPTCHA verifications; the resulting PowerShell command downloads a ZIP with legitimate LockScreenContentServer.exe and rogue dui70.dll for DLL sideloading, retrieves payloads hidden in PNG images from attacker domains, persists via Registry Run keys and scheduled tasks, and performs domain trust and Active Directory reconnaissance. A Python-based reverse-tunnel implant (client.py) tunnels arbitrary TCP traffic over an encrypted WebSocket to gitnow[.]dev:443, giving attackers network-level proxy access that could enable privilege escalation, security-tool tampering, data theft or ransomware. Microsoft recommends AppLocker restrictions, PowerShell script block logging and ClickFix awareness training.