Epoch's GLM 5.3 Built Real Firefox Exploits From Public Patches for $1,000

Epoch AI reports that the open-weight GLM 5.3 turned public Firefox patches into working one-click exploits for six consecutive releases, at about $1,000 per version once the test harness was ready. Each exploit used a webpage that could read a local file and send it to an attacker, and the work also rediscovered an unpublished sandbox escape that Mozilla later fixed in Firefox 159. It matters because it shows the gap between public fixes and stable releases can be exploited cheaply by an open model, while Chrome resisted the same approach in Epoch's tests.

• Alpha Signal2026-10-29 21:40