Perplexity Comet agentic browser vulnerable to zero-click agent hijacking and credential theft

Mar 2026

Zenity Labs disclosed PleaseFix, a family of critical vulnerabilities in Perplexity's Comet agentic browser that allowed zero-click agent hijacking, local file exfiltration, and credential theft. A malicious calendar invite could trigger the browser's AI agent to autonomously access the local file system and send contents to an attacker-controlled server without any user interaction. A second exploit abused agent-authorized workflows to steal credentials from 1Password vaults or achieve full account takeover. Perplexity patched the underlying issue before public disclosure.