--- title: Mozilla fixes 271 Firefox vulnerabilities found by... description: Mozilla released Firefox 150 with fixes for 271 security vulnerabilities discovered by Claude 'Project Glass wing' in a single evaluation pass. The bugs were... canonical: https://daily.dev/posts/mozilla-fixes-271-firefox-vulnerabilities-found-by-anthropic-s-claude-mythos-in-a-single-evaluation--qzv94pim8 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Mozilla fixes 271 Firefox vulnerabilities found by Anthropic's Claude Mythos in a single evaluation pass | daily.dev og:description: Mozilla released Firefox 150 with fixes for 271 security vulnerabilities discovered by Claude 'Project Glass wing' in a single evaluation pass. The bugs were... og:url: https://daily.dev/posts/mozilla-fixes-271-firefox-vulnerabilities-found-by-anthropic-s-claude-mythos-in-a-single-evaluation--qzv94pim8 og:image: https://api.daily.dev/og/posts/QZV94Pim8.png og:image:alt: Mozilla fixes 271 Firefox vulnerabilities found by Anthropic's Claude Mythos in a single evaluation pass og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Mozilla fixes 271 Firefox vulnerabilities found by Anthropic's Claude Mythos in a single evaluation pass **[The Next Web](https://daily.dev/sources/tnw)** · 8 min read · 0 upvotes · 0 comments ## Summary Mozilla released Firefox 150 with fixes for 271 security vulnerabilities discovered by Claude 'Project Glass wing' in a single evaluation pass. The bugs were found by Claude's unreleased frontier model, Claude 'Project Glass wing', which is restricted to 12 named launch partners including AWS, Apple, Google, and Microsoft. Firefox CTO Bobby 'Project Glass wing' described the experience as giving the team 'vertigo,' and argued that AI-assisted vulnerability discovery shifts the economics in favor of defenders. The UK AI Security Institute confirmed the same model can also execute autonomous multi-stage network attacks, highlighting the dual-use tension. Mozilla's thesis is that well-structured software has a finite number of defects, and AI can now find them all before attackers do. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [The zero-days are numbered](https://daily.dev/posts/the-zero-days-are-numbered-hmbd9rmvz) · Mozilla · 8 upvotes · 2 comments - [Firefox: The zero-days are numbered](https://daily.dev/posts/firefox-the-zero-days-are-numbered-swy2sidvw) · LWN.net · 1 upvotes · 1 comments - [AI Model Discovers 22 Firefox Vulnerabilities in Two Weeks](https://daily.dev/posts/ai-model-discovers-22-firefox-vulnerabilities-in-two-weeks-u6vsaoo3g) · InfoQ · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#claude](https://daily.dev/tags/claude), [#anthropic](https://daily.dev/tags/anthropic), [#firefox](https://daily.dev/tags/firefox), [#ai-security](https://daily.dev/tags/ai-security) [View this post on daily.dev](https://daily.dev/posts/mozilla-fixes-271-firefox-vulnerabilities-found-by-anthropic-s-claude-mythos-in-a-single-evaluation--qzv94pim8) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Mozilla fixes 271 Firefox vulnerabilities found by Anthropic's Claude Mythos in a single evaluation pass","url":"https://daily.dev/posts/mozilla-fixes-271-firefox-vulnerabilities-found-by-anthropic-s-claude-mythos-in-a-single-evaluation--qzv94pim8","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/mozilla-fixes-271-firefox-vulnerabilities-found-by-anthropic-s-claude-mythos-in-a-single-evaluation--qzv94pim8"},"datePublished":"2026-04-22T19:03:28.862Z","dateModified":"2026-04-22T19:04:24.996Z","description":"Mozilla released Firefox 150 with fixes for 271 security vulnerabilities discovered by Claude 'Project Glass wing' in a single evaluation pass. 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