CVE-2026-41495 n8n-MCP Logs Sensitive Request Data on Unauthorized /mcp Requests
Attackers with log access can view sensitive tokens and API keys from rejected requests in n8n-MCP HTTP mode deployments.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-41495?
CVE-2026-41495 is a medium-severity vulnerability in czlonkowski n8n-mcp, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-532
Which versions are affected by CVE-2026-41495?
2 open source packages ship an affected version, including n8n-mcp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
n8n-mcp npm | All versions | 2.47.11 |
n8n-mcp npm | All versions | 2.47.11 |
Products include N8n-Mcp N8n-Mcp.
How do I fix CVE-2026-41495?
Upgrade n8n-mcp to 2.47.11 or later.
Is CVE-2026-41495 being exploited?
There is no known exploitation of CVE-2026-41495 in the wild and no public exploit code.
Other vulnerabilities in czlonkowski n8n-mcp
- CVE-2026-54052 n8n-MCP: Cross-tenant access to workflow version backups in multi-tenant HTTP deployments
- CVE-2026-42449 n8n-MCP: IPv4-mapped IPv6 addresses bypass SSRF protection in validateUrlSync(), enabling full SSRF for SDK embedders
- CVE-2026-39974 n8n-MCP has an Authenticated SSRF via instance-URL header in multi-tenant HTTP mode
- CVE-2026-45707 n8n-MCP: Multi-tenant MCP requests fall back to process-level n8n credentials when tenant headers are absent or incomplete
- CVE-2026-44694 n8n-MCP: Authenticated SSRF in n8n-mcp webhook and API client paths
Sources
Also known as GHSA-pfm2-2mhg-8wpx.