Google Chrome Extension Harvests AI Chat Data from Millions of Users

Koi Security’s research revealed that the Urban VPN Proxy Chrome extension, which claims to enhance security and privacy, is actually intercepting and collecting data from AI chat platforms such as OpenAI’s ChatGPT, Google’s Gemini, Anthropic’s Claude, and Microsoft’s Copilot. This extension, which has over 6 million users and a 4.7-star rating, began harvesting AI chat conversations after its version 5.5.0 update on July 9, 2025. It collects not only user prompts but also chatbot responses, conversation identifiers, and session metadata, sharing this information with third parties like advertisers and data brokers.

Researchers identified similar functionalities in seven other extensions from the same publisher, increasing the total number of exposed users to 8 million. The extension injects a script into the AI chat platforms, allowing it to capture and exfiltrate conversation data before it is rendered in the user’s browser. This technique represents a significant breach of user trust, as many users install extensions believing they enhance their online privacy.

The incident raises concerns about the security of browser extensions, which often require extensive permissions that can be exploited. Users may not realize that these extensions can access sensitive data, including web traffic and saved credentials. As highlighted by Koi’s Dardikman, browser extensions occupy a unique position of trust and can easily misuse that trust.

Legitimate extensions can become malicious over time, as seen with Urban VPN Proxy, which initially did not harvest AI conversations. This pattern mirrors previous cases like ShadyPanda, where seemingly legitimate extensions were weaponized after gaining user trust. Users should be cautious about the permissions they grant to browser extensions and regularly review their installed extensions for any suspicious activity.

Google’s approval of the Urban VPN Proxy extension, despite its malicious behavior, underscores the need for better oversight in browser marketplaces. The fact that this extension passed a manual review and earned a Featured badge while harvesting sensitive data raises questions about the effectiveness of current vetting processes.