Epoch AI gave an open-weight model a browser, and it built working exploits on its own
AspireAI community · Epoch AI
*Epoch AI gave an open-weight model a browser, and it built working exploits on its own.*
GLM 5.3, released by Z.ai in August, read Firefox security fixes that Mozilla had published but not yet shipped, picked the vulnerabilities, and chained them into a page that could read a visitor's local file the moment they loaded it. Every Firefox build released between 17 September and 26 October was compromised, at roughly $1,000 per attack once the test rig existed.
It also found an unpublished bug that let it break out of the browser sandbox. Mozilla shipped Firefox 159.0 on 27 October to patch that one.
The honest limit: Epoch describes this as their own setup, not a Mozilla breach, and the same attack failed against Chrome.
https://epoch.ai/publications/open-weight-models-patch-gap
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