--- title: February 2026 Security Releases · Express.js | daily.dev description: Multer, the file-upload middleware maintained by the Express.js team, has received a security patch fixing two high-severity denial-of-service vulnerabilities.... canonical: https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: February 2026 Security Releases · Express.js | daily.dev og:description: Multer, the file-upload middleware maintained by the Express.js team, has received a security patch fixing two high-severity denial-of-service vulnerabilities.... og:url: https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu og:image: https://api.daily.dev/og/posts/vnBN7eieU.png og:image:alt: February 2026 Security Releases · Express.js 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. # February 2026 Security Releases · Express.js **[Express.js](https://daily.dev/sources/expressjs-blog)** · 1 min read · 0 upvotes · 0 comments ## Summary Multer, the file-upload middleware maintained by the Express.js team, has received a security patch fixing two high-severity denial-of-service vulnerabilities. CVE-2026-3304 involves incomplete cleanup that can cause resource exhaustion via malformed requests, while CVE-2026-2359 involves resource exhaustion triggered by dropped connections during file upload. Both affect versions below 2.1.0, and users are urged to upgrade immediately. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What versions of multer are affected by CVE-2026-3304 and CVE-2026-2359? Multer versions before 2.1.0 are vulnerable to both CVEs. CVE-2026-3304 is a denial-of-service issue caused by incomplete cleanup that leads to resource exhaustion from malformed requests, while CVE-2026-2359 is a denial-of-service triggered by dropped connections during file upload. The patched version is 2.1.0 or later. _Teams patching upload middleware can track multer CVE fixes like these on daily.dev._ ### Why should I upgrade multer to 2.1.0 or later? Multer versions below 2.1.0 contain two high-severity denial-of-service vulnerabilities: one from incomplete cleanup on malformed requests (GHSA-xf7r-hgr6-v32p) and another from resource exhaustion when connections drop during file upload (GHSA-v52c-386h-88mc). Both are fixed in version 2.1.0, which Express maintainers recommend applying immediately to secure applications. _daily.dev helps developers stay ahead of DoS advisories affecting Node.js middleware like multer._ ## Similar posts on daily.dev - [July 2026 Security Releases · Express.js](https://daily.dev/posts/july-2026-security-releases-express-js-tcsj3rcgu) · Express.js · 1 upvotes · 1 comments - [August 2026 Security Releases · Express.js](https://daily.dev/posts/august-2026-security-releases-express-js-kdzxqxlti) · Express.js · 2 upvotes · 0 comments - [September 2026 Security Releases · Express.js](https://daily.dev/posts/september-2026-security-releases-express-js-ivoho9puc) · Express.js · 1 upvotes · 0 comments - [Node.js — Node.js 26.5.1 \(Current\)](https://daily.dev/posts/node-js-node-js-26-5-1-current--hx951gecs) · Node.js · 25 upvotes · 0 comments - [Next.js May 2026 security release](https://daily.dev/posts/next-js-may-2026-security-release-hmqrmcava) · Vercel · 131 upvotes · 4 comments --- Tags: [#security](https://daily.dev/tags/security), [#cyber](https://daily.dev/tags/cyber), [#nodejs](https://daily.dev/tags/nodejs) [View this post on daily.dev](https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu) ```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":"February 2026 Security Releases · Express.js","url":"https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu"},"datePublished":"2026-08-23T12:17:25.380Z","dateModified":"2026-08-23T12:23:43.049Z","description":"Multer, the file-upload middleware maintained by the Express.js team, has received a security patch fixing two high-severity denial-of-service vulnerabilities....","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/a108f852597dd0bfe75e3ff8ff328750?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/a108f852597dd0bfe75e3ff8ff328750?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Express.js","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":"Express.js","logo":"https://media.daily.dev/image/upload/s--NvBVN7aT--/f_auto,q_auto/v1787487436/logos/expressjs-blog?_a=BAMAMicg0","url":"https://daily.dev/sources/expressjs-blog"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"security,cyber,nodejs","timeRequired":"PT1M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Express.js","item":"https://daily.dev/sources/expressjs-blog"},{"@type":"ListItem","position":3,"name":"February 2026 Security Releases · Express.js"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/february-2026-security-releases-express-js-vnbn7eieu#faq","mainEntity":[{"@type":"Question","name":"What versions of multer are affected by CVE-2026-3304 and CVE-2026-2359?","acceptedAnswer":{"@type":"Answer","text":"Multer versions before 2.1.0 are vulnerable to both CVEs. 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