HashJack Attack Uses URL ‘#’ to Control AI Browser Behavior

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November 29, 2025 at 2:03 PM

Summary

Cato Networks has identified a new vulnerability known as HashJack, which exploits the '#' symbol in URLs to execute malicious commands in AI browsers. While Microsoft and Perplexity have addressed this flaw, Google's Gemini remains vulnerable, highlighting a significant risk for users of that platform.

Original Article Summary

Cybersecurity firm Cato Networks reveals HashJack, a new AI browser vulnerability using the '#' symbol to hide malicious commands. Microsoft and Perplexity fixed the flaw, but Google's Gemini remains at risk.

Impact

Google's Gemini AI browser

In the Wild

Unknown

Timeline

Newly disclosed

Remediation

Microsoft and Perplexity have released fixes; specific details for Google's Gemini remediation are not provided.

Read Original Article

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