Millions of Enterprises at Risk: SquareX Shows How Malicious Extensions Bypass Google’s MV3 Restrictions

SquareX presented research at DEF CON showing that malicious Chrome extensions can still bypass Manifest V3 protections to steal sensitive data (site cookies, browsing history, bookmarks, live video streams), act on behalf of users (e.g., add collaborators to private repos), hook login flows to capture credentials, and push malicious downloads; the report warns enterprises that current EDR/SSE/SWG tools lack visibility into extensions and describes SquareX’s Browser Detection and Response product as a mitigation.