Understanding the Critical n8n-MCP Vulnerability
n8n-MCP is a server that helps AI assistants access documentation, properties, and operations for n8n nodes. A serious security flaw, identified as CVE-2026-54052, has been discovered in n8n-MCP. This vulnerability could allow unauthorized access and manipulation of sensitive user data in multi-tenant setups.
CVE Details
- Product: n8n-MCP
- Published Date: July 15, 2026
- Severity: CRITICAL
- Status: Analyzed
Affected Products
The vulnerability impacts versions of n8n-MCP released prior to 2.56.1. Specifically, if n8n-mcp was running in HTTP mode with multi-tenancy enabled (ENABLE_MULTI_TENANT=true), local workflow version history backups were not properly separated for each tenant.
This oversight meant that an authenticated user on the system could view workflow snapshots belonging to other tenants. Worse, they could delete or permanently destroy these stored backups. The exposed information could include complete node definitions, references to credentials, and authorization headers, which are all highly sensitive data.
Current Status
This vulnerability has been thoroughly analyzed. Details regarding the issue and its resolution are publicly available, allowing affected users to take necessary action.
Severity Level
Rated as CRITICAL, this vulnerability poses a significant risk. Its exploitation could lead to severe data breaches, unauthorized data manipulation, and a complete compromise of tenant data integrity and confidentiality within affected n8n-MCP installations.
Possible Solutions
The good news is that a fix is available. To protect your n8n-MCP instance from this critical vulnerability, you must update to version 2.56.1 or newer immediately. This update addresses the core issue by ensuring that workflow versions are properly scoped per instance, thereby isolating data between tenants.
References
https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.56.1
https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-j6r7-6fhx-77wx
