Claude Dispatch flaw can let browser extensions run system commands

Anthropic's Claude Dispatch contains a vulnerability that can let browser extensions direct Claude Desktop to run system commands, The Register reports. The attack can reach another computer signed into the same Claude account if Dispatch connects the devices.

Forever Security researcher Gal Weizman found that a browser extension with access to an authenticated Claude web session could issue commands through the Dispatch interface and API. The user must also be signed into Claude Desktop, while the relevant remote session must be available. His proof of concept used Claude to install a malicious npm package that opened the calculator application.

Anthropic recognized the report as a valid vulnerability in May but closed it as a duplicate of an existing issue. The company told Weizman it planned to retire Dispatch at the end of October, but its support page still listed the feature as available to existing users on October 30. Weizman said the same session sharing design is also present in Claude Code Remote Control and Claude Cowork.