#firefox

Anthropic said Claude Opus 4.6 found 22 Firefox vulnerabilities during a two-week collaboration with Mozilla. Mozilla classified 14 as high severity and shipped fixes in Firefox 148.0.

Anthropic said on March 6, 2026 that Claude Opus 4.6 uncovered 22 Firefox vulnerabilities in two weeks, including 14 high-severity issues, during a collaboration with Mozilla. The accompanying write-up argues that frontier models are becoming materially useful for real vulnerability discovery, not just benchmark performance.

The Anthropic-Mozilla collaboration that spread on Hacker News disclosed that Claude Opus 4.6 found 22 Firefox vulnerabilities, 14 of them high-severity. The durable lesson is not autonomous magic but faster defender workflows built around validation, triage, and reproducible evidence.

Anthropic published a March 6, 2026 case study showing how Claude Opus 4.6 authored a working test exploit for Firefox vulnerability CVE-2026-2796. The company presents the result as an early warning about advancing model cyber capabilities, not as proof of reliable real-world offensive automation.

Mozilla Firefox 148 debuts an 'AI Kill Switch' that lets users permanently disable all AI features in the browser, with the setting persisting across future updates. The release also includes new web security APIs and accessibility improvements.