CVE-2026-54052CWE-639CWE-862

n8n-MCP: Cross-tenant access to workflow version backups in multi-tenant HTTP deployments

Critical · published July 15, 2026

CVSS v3.1
9.9
EPSS
0%
Percentile
31.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.9 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
CVSS v4.0
Not supplied
EPSS
0.00388 · 31.7th percentile
Weaknesses
CWE-639 · Authorization Bypass Through User-Controlled Key; CWE-862 · Missing Authorization
Published
2026-07-15T20:34Z
EPSS history
Timeline
  • 15 JUL 20:34Z
    n8n-MCP: Cross-tenant access to workflow version backups in multi-tenant HTTP deployments
    cvelistv5