Anthropic's Claude Code AI Agent Leaked User Emails to Websites Without Consent

Multiple users of Anthropic's Claude Code AI programming tool reported that the agent shared their email addresses with arbitrary websites during web searches, resulting in a surge of spam messages. The leakage occurred through the User-Agent request header and by embedding the logged-in user's email directly into the system prompt for each session. Complaints appeared on GitHub and Hacker News over several months, with users noting a clear increase in scam emails after switching from tools like Copilot. The behavior was not presented as an optional setting and occurred without any user approval. On 2 November 2026, Anthropic released version 2.1.317 that added a permission prompt before transmitting the account email to external parties. The incident highlights risks of unintended data exposure in AI agents that perform autonomous web interactions.

Security.NLTranslated from NL

Read at source

Anthropic's Claude Code AI programming agent transmitted users' email addresses to third-party websites without consent, causing widespread spam complaints.

Users discovered that during web searches the tool included their email in the User-Agent request header. Additional reports indicated that Claude Code extracted the email of logged-in accounts and appended it to the model’s system prompt for every session before sending requests to external sites.

Multiple bug reports were filed on GitHub over recent months, with users stating they received dozens of scam emails daily after adopting the tool. One user noted a sharp rise in spam on their work mailbox compared with previous use of Copilot. Similar confirmations appeared on Hacker News.

Users argued that exposing account emails should never be an optional feature and should not occur at all. On 2 November 2026, Anthropic released version 2.1.317, which now prompts for explicit permission before forwarding the email address to websites or other parties.

Meridian digestThe week's most consequential security stories, distilled into one briefing.See the digest

More in AI & Model Risk

Agentic AI Becomes Operational Risk When Treated Like Administrators
Essential AI Skills Security Professionals Need Today
Cisco Open Sources Project Quarry to Detect Rogue AI Agent Behavior