Claude Opus 4.6 found more high-severity bugs in Firefox over a two-week period than the rest of the world typically reports in two months. The model discovered more than 100 bugs in total, 14 that were tagged as high severity. The model was asked to write code to exploit the bugs, but it turns out the model is much better at finding bugs than exploiting them. The exploits that Claude wrote would have been stopped in the real world by Firefox’s other security mechanisms.
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