SSRF in Czlonkowski N8n-Mcp
CVE-2026-44694
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. From version 2.18.7 to before version 2.50.2, there is an authenticated server-side request forgery vulnerability affecting the webhook trigger tools, the n8n API client (N8N_API_URL), and per-request URLs supplied via the x-n8n-url header in multi-tenant HTTP mode. This issue has been patched in version 2.50.2.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L.
EPSS exploit prediction
EPSS: 0.003 (21.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Czlonkowski N8n-Mcp — versions >= 2.18.7, < 2.50.2
- N8n-Mcp
Weakness classification (CWE)
References
- github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-cmrh-wvq6-wm9r (Mitigation, Vendor Advisory)
- github.com/czlonkowski/n8n-mcp/commit/bcaba839409d470abeb4a6ad9b361b553a1098eb (Patch)
- github.com/czlonkowski/n8n-mcp/releases/tag/v2.50.2 (Product, Release Notes)
Frequently asked questions
- What is CVE-2026-44694?
- CVE-2026-44694 is a critical-severity vulnerability in Czlonkowski N8n-Mcp, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 9.1/10. Published 2026-05-08.
- How severe is CVE-2026-44694?
- Critical severity. CVSS v3 base score is 9.1 out of 10.