czlonkowski n8n-mcp up to 2.56.0 Workflow Version History Backup improper authorization

Summaryinfo

A vulnerability has been found in czlonkowski n8n-mcp up to 2.56.0 and classified as critical. Impacted is an unknown function of the component Workflow Version History Backup. This manipulation causes improper authorization. This vulnerability is tracked as CVE-2026-54052. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability has been found in czlonkowski n8n-mcp up to 2.56.0 and classified as critical. Affected by this vulnerability is an unknown part of the component Workflow Version History Backup. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE 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 advisory is shared at github.com. This vulnerability is known as CVE-2026-54052 since 06/11/2026. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

Upgrading to version 2.56.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• czlonkowski

Name

• n8n-mcp

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.40
• 2.41
• 2.42
• 2.43
• 2.44
• 2.45
• 2.46
• 2.47
• 2.48
• 2.49
• 2.50
• 2.51
• 2.52
• 2.53
• 2.54
• 2.55
• 2.56.0

Website

• Product: https://github.com/czlonkowski/n8n-mcp/

CPE 2.3info

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CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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