AI agent incident

Zenity found zero-click hijacks of Claude and ChatGPT Atlas through emails and X posts

Reported August 6, 2026 · 1 source

What happened

Zenity researchers disclosed zero-click prompt injection flaws that let attackers hijack Claude and ChatGPT Atlas browser agents through emails and posts on X. They reported the flaws had been outstanding since late 2025 without a patch.

Why it matters

Two independent research efforts reached the same conclusion about browser agents within a fortnight, and this one needed no user interaction at all.

Sources

SecurityWeek Zero-Click AI Browser Hacking: Claude and ChatGPT Atlas Hijacked via Emails, X Posts August 6, 2026

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Background reading

Prompt injection The glossary definition, in plain English.

Cite or correct this record

“Zenity found zero-click hijacks of Claude and ChatGPT Atlas through emails and X posts.” The Permission Layer AI Agent Incident Database, https://thepermissionlayer.com/incidents/zenity-zero-click-browser-hijack/. Database updated October 22, 2026.

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