CVE-2026-54052
CriticalCVSS 9.9Exploitation Probability (EPSS)
Low risk31th percentile - higher than 31% of all known CVEs
Summary
In n8n-MCP prior to version 2.56.1, in HTTP mode with multi-tenancy enabled (ENABLE_MULTI_TENANT=true), local workflow version history backups were not isolated per tenant. This allowed an authenticated tenant to read and delete backups of other tenants, including full node definitions, credential references, and authorization headers.
Risk Assessment
The organization is at risk of confidential data leakage (node definitions, credentials, authorization headers) and loss of workflow backups belonging to other tenants, potentially compromising system integrity and confidentiality.
Recommendation
Immediately update n8n-MCP to version 2.56.1 or later. Until the update, consider disabling multi-tenancy (ENABLE_MULTI_TENANT=false) or restricting access to the MCP server.
Other vulnerabilities in n8n-MCP
See all- CVE-2026-42449High
In versions 2.47.4 through 2.47.13, n8n-MCP has a vulnerability related to the lack of IPv6 address validation in the URL validation function. An attacker can exploit this flaw to send HTTP requests to unauthorized endpoints, leading to data exposure.
- CVE-2026-44694Critical
n8n-MCP, an MCP server, has an authenticated server-side request forgery vulnerability affecting webhook trigger tools and the n8n API client. This issue exists in versions from 2.18.7 to before 2.50.2 and has been patched in version 2.50.2.
- CVE-2026-55608Medium
In n8n-MCP prior to version 2.57.4, multi-tenant HTTP mode with ENABLE_MULTI_TENANT=true could allow an authenticated tenant to access default-scope workflow_versions backups instead of being confined to the tenant scope, exposing or deleting workflow-version backups from prior single-tenant deployments or migrations.
- CVE-2026-45707High
In n8n-MCP prior to 2.51.2, when ENABLE_MULTI_TENANT=true, HTTP requests without x-n8n-url or x-n8n-key headers silently fell back to the operator's credentials, allowing an authenticated MCP tenant to execute n8n management calls against the operator's instance instead of its own.
- CVE-2026-45582Medium
In n8n-MCP prior to 2.51.3, the workflow telemetry sanitizer could retain partial fragments of URL-shaped node parameters, such as customer identifiers or secrets in query strings, before sending data to the anonymous telemetry backend. This is fixed in version 2.51.3.
Original NVD description (English source)
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.