CVE-2025-59155
hackmd-mcp server-side request forgery in HTTP transport mode
Description
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.
INFO
Published Date :
Sept. 15, 2025, 5:15 p.m.
Last Modified :
June 17, 2026, 9:45 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2025-59155
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update hackmd-mcp to version 1.5.0 or later.
- Switch to stdio transport mode if possible.
- Restrict outbound network access.
- Filter Hackmd-Api-Url header and query parameters.
Public PoC/Exploit Available at Github
CVE-2025-59155 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-59155.
| URL | Resource |
|---|---|
| https://github.com/yuna0x0/hackmd-mcp/commit/43936c78a5bb3dedc74e8f080607a1125caa8c13 | |
| https://github.com/yuna0x0/hackmd-mcp/security/advisories/GHSA-g5cg-6c7v-mmpw |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-59155 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-59155
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
The Project shares all information on MCP related CVE's published
mcp mcp-security mcp-cve
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-59155 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-59155 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'yuna0x0', 'product': 'hackmd-mcp', 'versions': [{'status': 'affected', 'version': '>= 1.4.0, < 1.5.0'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2025-59155', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2025-09-15T17:30:10.755995Z'} -
New CVE Received by [email protected]
Sep. 15, 2025
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-918 Added Reference https://github.com/yuna0x0/hackmd-mcp/commit/43936c78a5bb3dedc74e8f080607a1125caa8c13 Added Reference https://github.com/yuna0x0/hackmd-mcp/security/advisories/GHSA-g5cg-6c7v-mmpw