CVE-2026-54052 | BDVDB-2026-348671 Detail

czlonkowskin8n-mcp

Description#

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.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact low. Attack vector: network.

Weaknesses#

CWE-639 Authorization Bypass Through User-Controlled Key
CWE-862 Missing Authorization

References#

Exploit#

No public exploit known

History#

Version 12026-07-15Record published in the CVE List.
Version 22026-07-18Most recent update recorded in the CVE List.

Published

Published: 2026-07-15
Last modified: 2026-07-18

Vendor information

Vendor: czlonkowski
Product: n8n-mcp

All czlonkowski vulnerabilities

Score

9.9 Critical

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 33.2.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Insecure Direct Object Reference

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 2.56.1
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

9.9 Critical

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Privileges Required	Low
User Interaction	None
Scope	Changed
Confidentiality	High
Integrity	High
Availability	Low

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).