CVE-2026-41495

n8n-MCP Logs Sensitive Request Data on Unauthorized /mcp Requests

Published May 8, 2026 CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to version 2.47.11, when n8n-mcp runs in HTTP transport mode, incoming requests to the POST /mcp endpoint had their request metadata written to server logs regardless of the authentication outcome. In deployments where logs are collected, forwarded to external systems, or viewable outside the request trust boundary (shared log storage, SIEM pipelines, support/ops access), this can result in disclosure of: bearer tokens from the Authorization header, per-tenant API keys from the, x-n8n-key header in multi-tenant setups, JSON-RPC request payloads sent to the MCP endpoint. Access control itself was not bypassed — unauthenticated requests were correctly rejected with 401 Unauthorized — but sensitive values from those rejected requests could still be persisted in logs. This issue has been patched in version 2.47.11.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-pfm2-2mhg-8wpx n8n-MCP Logs Sensitive Request Data on Unauthorized /mcp Requests
History
Type Values Removed Values Added
First Time appeared N8n-mcp
N8n-mcp n8n-mcp
CPEs cpe:2.3:a:n8n-mcp:n8n-mcp:*:*:*:*:*:*:*:*
Vendors & Products N8n-mcp
N8n-mcp n8n-mcp
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Czlonkowski
Czlonkowski n8n-mcp
Vendors & Products Czlonkowski
Czlonkowski n8n-mcp
Type Values Removed Values Added
Description n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to version 2.47.11, when n8n-mcp runs in HTTP transport mode, incoming requests to the POST /mcp endpoint had their request metadata written to server logs regardless of the authentication outcome. In deployments where logs are collected, forwarded to external systems, or viewable outside the request trust boundary (shared log storage, SIEM pipelines, support/ops access), this can result in disclosure of: bearer tokens from the Authorization header, per-tenant API keys from the, x-n8n-key header in multi-tenant setups, JSON-RPC request payloads sent to the MCP endpoint. Access control itself was not bypassed — unauthenticated requests were correctly rejected with 401 Unauthorized — but sensitive values from those rejected requests could still be persisted in logs. This issue has been patched in version 2.47.11.
Title n8n-MCP Logs Sensitive Request Data on Unauthorized /mcp Requests
Weaknesses CWE-532
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
May 13, 2026, 5:47 PM
Reserved
Apr 20, 2026, 4:14 PM
Status
Analyzed
Published
May 8, 2026, 8:16 PM
Modified
Oct 26, 2026, 6:10 PM