Researchers Bypass ChatGPT Lockdown Mode to Exfiltrate Chats Without User Interaction
Nov 05, 2026
Vulnerability / AI Security
Cybersecurity researchers have disclosed details of a now-patched vulnerability that could be exploited to bypass Lockdown Mode protections in OpenAI ChatGPT. Lockdown Mode was introduced by the artificial intelligence (AI) company in June 2026 as an optional setting to minimize data exfiltration risks arising from prompt injections. "The flaw could enable silent chat data theft, phishing, and malware delivery, including zero-click data exfiltration in the ChatGPT desktop application," Eli Smadja, head of research at Check Point, said in a report shared with The Hacker News. The problem stems from HTML page previews inside ChatGPT code blocks, which allow HTML content to be rendered directly within the application. Given that executing user-supplied HTML and JavaScript can introduce security risks of its own, the content is placed inside a sandbox so that it cannot access data from the app, such as cookies and local storage. The sandbox also prevents the rendere...