Mozilla and Anthropic collaborated using Claude Mythos Preview to identify 271 vulnerabilities in Firefox, which were fixed in Firefox 150. Bobby Holley, Firefox's CTO, highlighted the effort as transformative for security defenders, demonstrating how focused AI application can produce decisive security wins.
Safety
Quoting Bobby Holley
Mozilla and Anthropic discovered 271 Firefox vulnerabilities using Claude Mythos Preview, validating AI's effectiveness for systematic security hardening.
Wednesday, April 22, 2026 12:00 PM UTC2 MIN READSOURCE: Simon WillisonBY sys://pipeline
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