Mozilla boasts Mythos boosted Firefox bug cull

Mozilla reported fixing 423 Firefox security bugs in April, attributing many findings to AI-assisted analysis (Anthropic’s Mythos and other models) combined with improved middleware/harnesses; the write-up highlights several high-severity issues (including sandbox escapes and a 20-year-old heap use-after-free) and covers skepticism from security researchers who argue the improvements may come more from the harness than the models themselves.