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CVE-2025-59155

CVE-2025-59155 · hackmd-mcp server-side request forgery in HTTP transport mode

This page contains facts from public vulnerability sources. Check the original advisory before updating.

hackmd-mcp is a Model Context Protocol server for integrating HackMD's note-taking platform with AI assistants. From 1.4.0 to before 1.5.0, hackmd-mcp contains a server-side request forgery (SSRF) vulnerability when the server is run in HTTP transport mode. Arbitrary hackmdApiUrl values supplied via the Hackmd-Api-Url HTTP header or a base64-encoded JSON query parameter are accepted without validation, allowing attackers to redirect outbound API requests to internal network services, access internal endpoints, perform network reconnaissance, and bypass network access controls. The stdio transport mode is not affected because it only accepts stdio requests. The issue is fixed in version 1.5.0, which enforces allowed endpoints and supports the ALLOWED_HACKMD_API_URLS environment variable. Users should update to 1.5.0 or later or apply documented mitigations such as switching to stdio mode, restricting outbound network access, or filtering the Hackmd-Api-Url header and related query parameter via a reverse proxy.

CVSS 6.9 · Medium · EPSS 0.4% · Fix available

Published
Updated

Stack: node

Affected products and versions

  • hackmd-mcp

    Versions
    • >= 1.4.0, < 1.5.0: Affected

    No fix published

  • hackmd-mcp npm

    Affected ranges
    • SEMVER: ≥ 1.4.0, < 1.5.0

    Update to 1.5.0

Original sources

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