CVE-2025-5276: Markdownify MCP Server allows Server-Side Request Forgery (SSRF) via the Markdownify.get() function
All versions of the package mcp-markdownify-server are vulnerable to Server-Side Request Forgery (SSRF) via the Markdownify.get() function. An attacker can craft a prompt that, once accessed by the MCP host, can invoke the webpage-to-markdown, bing-search-to-markdown, and youtube-to-markdown tools to issue requests and read the responses to attacker-controlled URLs, potentially leaking sensitive information.
References
- github.com/advisories/GHSA-frq9-3hp2-xvxg
- github.com/zcaceres/markdownify-mcp
- github.com/zcaceres/markdownify-mcp/blob/224cf89f0d58616d2a5522f60f184e8391d1c9e3/src/server.ts
- github.com/zcaceres/markdownify-mcp/commit/0284aa8f34d32c65e20d8cda2d429b7943c9af03
- nvd.nist.gov/vuln/detail/CVE-2025-5276
- security.snyk.io/vuln/SNYK-JS-MCPMARKDOWNIFYSERVER-10249387
Code Behaviors & Features
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