Forever Security ThisBash: Browser Extension Can Drive Claude Desktop RCE via Dispatch, Even Cross-Machine
On 2026-11-04, Forever Security researcher Gal Weizman published ThisBash: a browser extension that can script claude.ai can abuse the still-reachable Claude Dispatch interface to send instructions as the signed-in user, auto-click Allow, and run code on Claude Desktop—including another machine paired to the same account. Anthropic validated the report in May and said Dispatch would retire, but the help page still lets existing users keep it.

Key Takeaways
- Source: Forever Security researcher Gal Weizman (2026-11-04) + The Hacker News / The Register; Anthropic validated in May, closed as internal duplicate
- Surface: a browser extension that can script claude.ai can drive Claude Desktop via Dispatch (hidden but reachable) and auto-click Allow
- PoC: four user-voice prompts + 1s Allow clicks → npm install -g; preinstall opened Calculator; no browser exploit needed
- Cross-device: another Desktop paired to the same Claude account is reachable; personal account on a work laptop can become org ingress
- Status: Anthropic said retire Dispatch by end of Oct; help page still lets existing users keep it; authors flag Remote Control / Cowork as same trust pattern
