--- title: they hacked CSS | daily.dev description: Chrome's first zero-day of the year (CVE-2026-2441, CVSS 8.8) is under active exploitation. The vulnerability is a use-after-free bug in Chrome's CSS font... canonical: https://daily.dev/posts/they-hacked-css-rtgo6ke0s twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: they hacked CSS | daily.dev og:description: Chrome's first zero-day of the year (CVE-2026-2441, CVSS 8.8) is under active exploitation. The vulnerability is a use-after-free bug in Chrome's CSS font... og:url: https://daily.dev/posts/they-hacked-css-rtgo6ke0s og:image: https://api.daily.dev/og/posts/RTgO6Ke0s.png og:image:alt: they hacked CSS 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. # they hacked CSS **[Low Level Learning](https://daily.dev/sources/lowlevellearning)** · 9 min read · 0 upvotes · 0 comments ## Summary Chrome's first zero-day of the year (CVE-2026-2441, CVSS 8.8) is under active exploitation. The vulnerability is a use-after-free bug in Chrome's CSS font feature value map parsing, written in C++. When JavaScript iterates over CSS font feature rules and deletes entries simultaneously, a dangling pointer can be exploited to achieve arbitrary code execution inside the browser sandbox. The patch replaces a reference-based iteration with a copy (move semantics) to prevent modification of the underlying map during traversal. The video explains use-after-free mechanics with a cat/dog struct analogy, demonstrates the concept in GDB, and discusses why Rust's ownership model would prevent this class of bug — noting Firefox's CSS renderer is already written in Rust. The immediate mitigation is simply updating Chrome to the latest version. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [CVE-2026-2441 Explained: CSS Zero-Day Browser Security](https://daily.dev/posts/cve-2026-2441-explained-css-zero-day-browser-security-3lvuhpbw0) · SitePoint · 1 upvotes · 0 comments - [Google patches new Chrome zero-day flaw exploited in the wild](https://daily.dev/posts/google-patches-new-chrome-zero-day-flaw-exploited-in-the-wild-tpectayr9) · BleepingComputer · 1 upvotes · 0 comments - [Zero-Day CSS: Deconstructing CVE-2026-2441 Security Vulnerability](https://daily.dev/posts/zero-day-css-deconstructing-cve-2026-2441-security-vulnerability-juwqctacy) · SitePoint · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#rust](https://daily.dev/tags/rust), [#google-chrome](https://daily.dev/tags/google-chrome) [View this post on daily.dev](https://daily.dev/posts/they-hacked-css-rtgo6ke0s) ```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":"they hacked CSS","url":"https://daily.dev/posts/they-hacked-css-rtgo6ke0s","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/they-hacked-css-rtgo6ke0s"},"datePublished":"2026-02-18T16:06:21.353Z","dateModified":"2026-02-22T16:58:47.706Z","description":"Chrome's first zero-day of the year (CVE-2026-2441, CVSS 8.8) is under active exploitation. 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