--- title: CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in... description: A heap-based buffer overflow vulnerability (CVE-2026-14266) in 7-Zip's XZ decompression code has been patched in version 26.02. The flaw, traced to the... canonical: https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in XZ Archives Since 2021 | daily.dev og:description: A heap-based buffer overflow vulnerability (CVE-2026-14266) in 7-Zip's XZ decompression code has been patched in version 26.02. The flaw, traced to the... og:url: https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2 og:image: https://api.daily.dev/og/posts/bFYx6nVg2.png og:image:alt: CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in XZ Archives Since 2021 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. # CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in XZ Archives Since 2021 **[Latest Hacking News](https://daily.dev/sources/lhn)** · 5 min read · 0 upvotes · 0 comments ## Summary A heap-based buffer overflow vulnerability (CVE-2026-14266) in 7-Zip's XZ decompression code has been patched in version 26.02. The flaw, traced to the MixCoder_Code function in C/XzDec.c, allowed a crafted XZ archive to execute arbitrary code upon extraction. It existed undetected from 7-Zip 21.07 (2021) through 26.01 — a five-year window. Discovered by Landon Peng of Lunbun LLC and rated CVSS 7.0 (High), exploitation requires user interaction: a victim must open or extract a malicious archive. No in-the-wild exploitation has been observed. Because 7-Zip lacks auto-update, organizations must manually push the patch and also check for embedded 7-Zip instances in third-party tools. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Hackers Actively Exploiting 7-Zip Symbolic Link–Based RCE Vulnerability \(CVE-2025-11001\)](https://daily.dev/posts/hackers-actively-exploiting-7-zip-symbolic-link-based-rce-vulnerability-cve-2025-11001--hzcl4jrdf) · The Hacker News · 0 upvotes · 0 comments - [Unbounded decompression in UnZipTransformer enables zip-bomb DoS](https://daily.dev/posts/unbounded-decompression-in-unziptransformer-enables-zip-bomb-dos-v39pvdof1) · Spring · 1 upvotes · 0 comments - [The “Unzip” of Death: Why Using Your Old WinRAR Is a Dangerous Trap](https://daily.dev/posts/the-unzip-of-death-why-using-your-old-winrar-is-a-dangerous-trap-bwbzk88fe) · InfoSec Write-ups · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security) [View this post on daily.dev](https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2) ```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":"CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in XZ Archives Since 2021","url":"https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2"},"datePublished":"2026-07-26T19:12:34.911Z","dateModified":"2026-07-26T19:12:54.772Z","description":"A heap-based buffer overflow vulnerability (CVE-2026-14266) in 7-Zip's XZ decompression code has been patched in version 26.02. The flaw, traced to the...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2d0aa9c12b8aa31fd7a1c61ae0da5235?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2d0aa9c12b8aa31fd7a1c61ae0da5235?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Latest Hacking News","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Latest Hacking News","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/5110318ded6e43f1bb12facdeb2b1965","url":"https://daily.dev/sources/lhn"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/cve-2026-14266-inside-the-7-zip-heap-overflow-hiding-in-xz-archives-since-2021-bfyx6nvg2","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"security","timeRequired":"PT5M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Latest Hacking News","item":"https://daily.dev/sources/lhn"},{"@type":"ListItem","position":3,"name":"CVE-2026-14266: Inside the 7-Zip Heap Overflow Hiding in XZ Archives Since 2021"}]} ```