--- title: Millions of AI agents imperiled by critical... description: A critical vulnerability dubbed 'BadHost' (CVE-2026-48710) has been discovered in Starlette, a Python ASGI framework with 325 million weekly downloads. The... canonical: https://daily.dev/posts/millions-of-ai-agents-imperiled-by-critical-vulnerability-in-open-source-package-s6y7fxdoe twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Millions of AI agents imperiled by critical vulnerability in open source package | daily.dev og:description: A critical vulnerability dubbed 'BadHost' (CVE-2026-48710) has been discovered in Starlette, a Python ASGI framework with 325 million weekly downloads. The... og:url: https://daily.dev/posts/millions-of-ai-agents-imperiled-by-critical-vulnerability-in-open-source-package-s6y7fxdoe og:image: https://api.daily.dev/og/posts/S6y7fXDOe.png og:image:alt: Millions of AI agents imperiled by critical vulnerability in open source package 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. # Millions of AI agents imperiled by critical vulnerability in open source package **[Ars Technica](https://daily.dev/sources/arstechnica)** · 2 min read · 11 upvotes · 0 comments ## Summary A critical vulnerability dubbed 'BadHost' (CVE-2026-48710) has been discovered in Starlette, a Python ASGI framework with 325 million weekly downloads. The flaw allows attackers to bypass path-based authorization by injecting a single character into the HTTP Host header. Because Starlette underpins FastAPI and many AI-related packages — including vLLM, LiteLLM, MCP servers, and agent harnesses — millions of AI agents and services are exposed. Attackers can breach servers and steal credentials stored by MCP servers. The vulnerability is trivially exploitable against systems not behind a properly configured firewall. A fix is available in Starlette 1.0.1, and an online scanner has been released to check server exposure. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: --- Tags: [#security](https://daily.dev/tags/security), [#python](https://daily.dev/tags/python), [#mcp](https://daily.dev/tags/mcp), [#fastapi](https://daily.dev/tags/fastapi) [View this post on daily.dev](https://daily.dev/posts/millions-of-ai-agents-imperiled-by-critical-vulnerability-in-open-source-package-s6y7fxdoe) ```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":"Millions of AI agents imperiled by critical vulnerability in open source package","url":"https://daily.dev/posts/millions-of-ai-agents-imperiled-by-critical-vulnerability-in-open-source-package-s6y7fxdoe","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/millions-of-ai-agents-imperiled-by-critical-vulnerability-in-open-source-package-s6y7fxdoe"},"datePublished":"2026-05-26T22:02:30.060Z","dateModified":"2026-06-05T15:06:15.118Z","description":"A critical vulnerability dubbed 'BadHost' (CVE-2026-48710) has been discovered in Starlette, a Python ASGI framework with 325 million weekly downloads. 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