CVE-2026-45707

n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 2.51.2, when ENABLE_MULTI_TENANT=true, the HTTP transport documents that the target n8n instance is selected per-request from x-n8n-url / x-n8n-key headers. Requests that omitted those headers — or supplied only one of them — silently fell back to the process-level N8N_API_URL / N8N_API_KEY credentials configured for the operator's own n8n instance. As a result, an authenticated MCP tenant could cause n8n management calls to execute against the operator's instance instead of its own. This affects HTTP-mode deployments of n8n-mcp that are run as a shared multi-tenant service. Single-tenant deployments (ENABLE_MULTI_TENANT unset or false) are not affected. This vulnerability is fixed in 2.51.2.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/czlonkowski/n8n-mcp/commit/853015d0897be7cf2d9d4726de195c938e4395ab	Patch
https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.51.2	Product Release Notes
https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-jxx9-px88-pj69	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:n8n-mcp:n8n-mcp:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-29 14:16

Updated : 2026-07-21 12:10

NVD link : CVE-2026-45707

Mitre link : CVE-2026-45707

CVE.ORG link : CVE-2026-45707

JSON object : View

Products Affected

n8n-mcp

n8n-mcp

CWE

CWE-284

Improper Access Control

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