Simon Willison notes that OpenAI’s previously teased Lockdown Mode is now live for eligible personal and self-serve Business ChatGPT accounts. The feature does not stop prompt injections from appearing in content, but limits outbound network requests that could leak sensitive data. He sees it as a direct mitigation for the exfiltration leg of the “Lethal Trifecta,” while implying default ChatGPT settings are not robust against determined data theft attempts.
Simon Willison summarizes a PromptArmor report about Microsoft Copilot Cowork and agentic data exfiltration risks. The issue involved agents sending messages to a user’s own inbox without approval, where rendered external images could trigger requests to attacker-controlled sites. Because OneDrive can create pre-authenticated download links, a successful prompt injection could leak links that allow attackers to download files.