Apr 21, 2026 2:30 PM

Mozilla Used Anthropic’s Mythos to Find and Fix 271 Bugs in Firefox

The Firefox team doesn’t think emerging AI capabilities will upend cybersecurity long term, but they warn that software developers are likely in for a rocky transition.

Photograph: SOPA Images/Getty Images

Amid a raging debate over the impact that new AI models will have on cybersecurity, Mozilla said on Tuesday that its Firefox 150 browser release this week includes protections for 271 vulnerabilities identified using early access to Anthropic's Mythos Preview. The Firefox team says that it has taken resources and discipline to adjust to the firehose of bugs that new AI tools can uncover, but that this big lift is necessary for the security of Mozilla’s users, given that the capabilities will inevitably be in attackers’ hands soon.

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Lily Hay Newman is a senior writer at WIRED focused on information security, digital privacy, and hacking. She previously worked as a technology reporter at Slate, and was the staff writer for Future Tense, a publication and partnership between Slate, the New America Foundation, and Arizona State University. Her work ... Read More

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