--- title: What is a dependency firewall? | daily.dev description: A dependency firewall is a security checkpoint that blocks malicious open-source packages before they install, functioning like a network firewall but for... canonical: https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: What is a dependency firewall? | daily.dev og:description: A dependency firewall is a security checkpoint that blocks malicious open-source packages before they install, functioning like a network firewall but for... og:url: https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j og:image: https://api.daily.dev/og/posts/o56l5Qo5J.png og:image:alt: What is a dependency firewall? 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. # What is a dependency firewall? **[Aikido Security](https://daily.dev/sources/aikido-security)** · 12 min read · 0 upvotes · 0 comments ## Summary A dependency firewall is a security checkpoint that blocks malicious open-source packages before they install, functioning like a network firewall but for package managers. Supply chain attacks have surged — Aikido Intel now flags up to 100,000 malicious packages daily. Key threats include postinstall hook exploits (e.g., the axios maintainer hijack in March 2026), AI coding agents installing hallucinated package names (slopsquatting), typosquatting, dependency confusion, and account takeovers of trusted maintainers. A capable dependency firewall checks for known malware, enforces minimum package age, detects obfuscation techniques, and inspects install script behavior — including for transitive dependencies. Aikido offers Safe Chain (free, open-source, wraps npm/yarn/pnpm/pip) and Device Protection (MDM-deployed, org-wide coverage) backed by the Aikido Intel threat feed. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What happened in the axios npm supply chain attack in March 2026? Attackers hijacked the axios maintainer's npm account and pushed two malicious versions of the library, which has around 100 million weekly downloads. The payload arrived through a newly added transitive dependency called plain-crypto-js, whose postinstall hook dropped a cross-platform remote access trojan (RAT) on any machine that ran the install. The malicious package existed for less than 24 hours before being pulled. _daily.dev surfaces incidents like this for developers auditing their own dependency trees for similar exposure._ ### Do npm, pnpm, yarn, and bun support a minimum package age setting to block newly published packages? Yes, every major package manager in the npm ecosystem now ships a minimum release age setting: pnpm, Yarn, Bun, and npm itself all support configuring a threshold that refuses to install any package version newer than that window. This closes the early-detection gap, since most malicious releases get caught and pulled within a day or two of publication. _developers picking a package manager configuration can track supply chain protections like this on daily.dev._ ### What was the first malicious MCP server found on npm? An attacker impersonating Postmark published a malicious MCP server to npm that quietly BCC'd every outgoing email to an attacker-controlled address, discovered in September 2025. It was the first confirmed malicious MCP server on npm, highlighting that coding agents and MCP servers pulling packages on developer machines are a newer, less-monitored install surface than direct npm installs. _teams securing AI agent workflows follow emerging MCP security risks like this on daily.dev._ ## Similar posts on daily.dev - [What Is a Dependency Firewall? – Open Source Security Foundation](https://daily.dev/posts/what-is-a-dependency-firewall-open-source-security-foundation-582oigusq) · OpenSSF · 0 upvotes · 0 comments - [Aikido Endpoint: Security for Developer Devices](https://daily.dev/posts/aikido-endpoint-security-for-developer-devices-suvvyswae) · Aikido Security · 0 upvotes · 0 comments - [Why npm dependencies are a bigger security risk than your code](https://daily.dev/posts/why-npm-dependencies-are-a-bigger-security-risk-than-your-code-zyi7hulam) · LogRocket · 0 upvotes · 0 comments - [How Aikido Intel detects malware and vulnerabilities first](https://daily.dev/posts/how-aikido-intel-detects-malware-and-vulnerabilities-first-vq06ha6jl) · Aikido Security · 0 upvotes · 0 comments - [Dependency Firewall: Block risky packages before the build](https://daily.dev/posts/dependency-firewall-block-risky-packages-before-the-build-s4en4pqa6) · GitLab · 0 upvotes · 0 comments --- Tags: [#security](https://daily.dev/tags/security), [#npm](https://daily.dev/tags/npm) [View this post on daily.dev](https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j) ```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":"What is a dependency firewall?","url":"https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j"},"datePublished":"2026-07-13T18:58:53.864Z","dateModified":"2026-09-13T20:28:38.437Z","description":"A dependency firewall is a security checkpoint that blocks malicious open-source packages before they install, functioning like a network firewall but for...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/1f103fc68ae915d094601eb01222b2a9?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/1f103fc68ae915d094601eb01222b2a9?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Aikido Security","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":"Aikido Security","logo":"https://media.daily.dev/image/upload/s--vJDqDYv_--/f_auto,q_auto/v1774959928/logos/aikido-security?_a=BAMAMiWQ0","url":"https://daily.dev/sources/aikido-security"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"security,npm","timeRequired":"PT12M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Aikido Security","item":"https://daily.dev/sources/aikido-security"},{"@type":"ListItem","position":3,"name":"What is a dependency firewall?"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/what-is-a-dependency-firewall--o56l5qo5j#faq","mainEntity":[{"@type":"Question","name":"What happened in the axios npm supply chain attack in March 2026?","acceptedAnswer":{"@type":"Answer","text":"Attackers hijacked the axios maintainer's npm account and pushed two malicious versions of the library, which has around 100 million weekly downloads. 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