Description
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 2.56.1, in HTTP mode with multi-tenancy enabled through ENABLE_MULTI_TENANT=true, n8n-mcp's local workflow version history backups were not isolated per tenant, allowing an authenticated tenant to read workflow version snapshots belonging to other tenants and delete or destroy other tenants' stored backups, including full node definitions, credential references, and authorization headers. This issue is fixed in version 2.56.1.
Affected products
n8n-mcp: n8n-mcp
References2
- github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-j6r7-6f… MitigationVendor Advisory
- github.com/czlonkowski/n8n-mcp/releases/tag/v2.56.1 Release Notes
Metrics
- CVSS 3.1
-
9.9
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L - EPSS — exploit probability
- 0% percentile: 33 · as of 15 November 2026
- CWE
- CWE-639CWE-862
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