Medium severity · published May 29, 2026
CVE-2026-45582
n8n-MCP: Workflow telemetry sanitizer could retain partial values from URL-shaped node parameters
6.5
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
N8
n8n-mcp · czlonkowski
< 2.51.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-45582
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-45582
Patch
https://github.com/czlonkowski/n8n-mcp/commit/6cf6fef653fcd6d598f2f356aac4754931c7329f
Issue Tracking
https://github.com/czlonkowski/n8n-mcp/pull/782
Product
https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.51.3
Mitigation
https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-f3rg-xqjj-cj9w
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