Medium severity · published Jul 15, 2026
CVE-2026-55608
n8n-MCP: Incorrect authorization can expose default-scope workflow version backups in multi-tenant HTTP mode
5.4
CVSS
0.3%
EPSS
No
On KEV
Description
n8n-MCP is an MCP server that provides AI assistants access to n8n node documentation, properties, and operations. Prior to 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. This issue is fixed in version 2.57.4.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
N8
n8n-mcp · czlonkowski
< 2.57.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55608
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55608
Patch
https://github.com/czlonkowski/n8n-mcp/commit/1f42899749ed0c584fb6b4fd63d75233c3edee59
Release Notes
https://github.com/czlonkowski/n8n-mcp/releases/tag/v2.57.4
Mitigation
https://github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-2cf7-hpwf-47h9
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