Server-side Request Forgery (SSRF) Affecting hackmd-mcp package, versions >=1.4.0 <1.5.0
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published16 Sept 2025
- disclosed15 Sept 2025
- creditUnknown
Introduced: 15 Sep 2025
CVE-2025-59155 (opens in a new tab)How to fix?
Upgrade hackmd-mcp to version 1.5.0 or higher.
Overview
hackmd-mcp is an A Model Context Protocol server for integrating HackMD's note-taking platform with AI assistants.
Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via the hackmdApiUrl parameter in HTTP transport mode. An attacker can access internal network resources, perform network reconnaissance, and bypass network access controls by supplying arbitrary values through the Hackmd-Api-Url HTTP header or a base64-encoded JSON query parameter.
Workarounds
Switch to stdio mode by setting
TRANSPORT=stdioor removing theTRANSPORTenvironment variable to disable HTTP mode.Restrict outbound server connections using firewalls or network policies.
Deploy a reverse proxy in front of the MCP server to validate and filter the
Hackmd-Api-Urlheader and the base64-encoded JSON config query parameter, blocking potentially dangeroushackmdApiUrlvalues.