Fake CAPTCHA Tricks Users Into Running Malware

TechSpot · High sophistication
Last updated September 3, 2026

Microsoft warns of a real malware campaign (“TerminalFix”) that uses fake CAPTCHA pages to convince people to open PowerShell or Command Prompt and paste attacker-provided commands. Because the user runs the command themselves, the attack can bypass many technical safeguards and can lead to deeper access into a company network.

Key findings

  • Attackers use fake CAPTCHA pages that impersonate trusted services (including Cloudflare) to instruct users to run system commands.
  • Victims are told to open PowerShell or Command Prompt and paste a command, enabling longer multi-line scripts than older “ClickFix” variants.
  • Once executed, the malware can enable a multi-stage intrusion and provide persistent proxy access into an enterprise network.
  • The campaign relies on user manipulation, not a hidden software exploit, making awareness training a key defense.
  • Microsoft recommends controls such as limiting PowerShell/Run access where possible and enabling Microsoft Defender cloud-delivered protection.

Who’s being targeted

  • Commonly targeted roles: All employees, IT administrators, Developers, Security operations, Helpdesk.
  • Affected industries: Enterprise (cross-industry).
  • Attack channels: website.
  • Impersonated: Cloudflare (or another trusted CAPTCHA/verification provider).

Awareness takeaways

  • Treat any CAPTCHA or “security check” that asks you to run PowerShell/Command Prompt/Run commands as malicious and stop immediately.
  • Coach staff that attackers may try to bypass security tools by getting users to execute code themselves.
  • Limit and monitor scripting tools (PowerShell/Run) to only the roles that truly need them, and watch for unusual command activity.
  • Emphasize enterprise impact: a single infected device can become a stepping stone to ransomware or broader compromise.

Red flags to watch for

  • A CAPTCHA asking you to open PowerShell/Command Prompt/Run dialog
  • Instructions to paste and run commands as part of a “verification” step
  • Impersonation of a trusted brand to add legitimacy
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Read the video transcript

You land on a site, see a Cloudflare-style CAPTCHA, and it says: "Verify you are human: open PowerShell and paste this command." This is a real attack called TerminalFix. The page impersonates Cloudflare, skips the normal image puzzle, and walks you step by step to open PowerShell or Command Prompt and run their code. Here’s the nasty part: because you paste it yourself, it can slip past some defenses, then quietly turn your laptop into a proxy into our network, paving the way for ransomware. Remember this rule: if any CAPTCHA or security check tells you to open PowerShell, Command Prompt, or Run and paste a command, stop and report it to IT immediately.

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