Claude AI Discovers 22 Firefox Vulnerabilities in Mozilla Collaboration, Including 14 High-Severity Issues
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Summary
Anthropic's Claude AI model discovered 22 vulnerabilities in Firefox during a two-week collaboration with Mozilla researchers, including 14 high-severity vulnerabilities that represent nearly 20% of all high-severity Firefox vulnerabilities fixed in 2025. The article details how AI models can independently identify security flaws in complex software, building on previous research where Claude found over 500 zero-day vulnerabilities in open-source software.
Key quotes
· 4 pulledAI models can now independently identify high-severity vulnerabilities in complex software.
Claude found more than 500 zero-day vulnerabilities (security flaws that are unknown to the software's maintainers) in well-tested open-source software.
Claude Opus 4.6 discovered 22 vulnerabilities over the course of two weeks.
Mozilla assigned 14 as high-severity vulnerabilities—almost a fifth of all high-severity Firefox vulnerabilities that were remediated in 2025.
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