April 22, 2026

Mozilla patched 271 Firefox bugs found by Anthropic’s Mythos, and says the zero-day era has an expiration date

a statue of an angel holding a cross
Bradley Gossett / Unsplash

Summary: Mozilla released Firefox 150 with fixes for 271 security vulnerabilities identified by Anthropic’s Claude Mythos Preview, an unreleased frontier AI model distributed under the restricted Project Glasswing programme. The collaboration began w...