Type: url
Original: https://simonwillison.net/2025/Jun/16/the-lethal-trifecta/
Status: generated
Summary
The post naming the “lethal trifecta”: the combination of access to private data, exposure to untrusted content, and the ability to communicate externally, which together let an attacker trick a tool-using LLM into exfiltrating a user’s data. It argues the danger is a property of the combination rather than of any single capability, that MCP makes the combination easy to assemble by accident, and that since vendors cannot protect a user who mixes their own tools, avoiding the combination is the only reliable remedy available to an end user.