Description
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 2.51.3, the workflow telemetry sanitizer could retain partial fragments of URL-shaped node parameters before sending workflow data to the project's anonymous telemetry backend. Values placed in HTTP-Request-style node parameters — such as customer or tenant identifiers, short secrets embedded in query strings, and signed request parameters — could therefore appear in stored telemetry, contrary to the collection boundary documented in PRIVACY.md. This vulnerability is fixed in 2.51.3.
Affected products
n8n-mcp: n8n-mcp
References4
- github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-f3rg-xq… MitigationVendor Advisory
- github.com/czlonkowski/n8n-mcp/commit/6cf6fef653fcd6d598f2f356a… Patch
- github.com/czlonkowski/n8n-mcp/pull/782 Issue TrackingPatch
- github.com/czlonkowski/n8n-mcp/releases/tag/v2.51.3 ProductRelease Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 18 · as of 15 November 2026
- CWE
- CWE-201
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