What is CVE-2026-55608?

CVE-2026-55608 is a medium-severity vulnerability in Czlonkowski N8n-Mcp, classified under Information Disclosure. CVSS score: 4.2/10. Published 2026-07-15.

How severe is CVE-2026-55608?

Medium severity. CVSS v3 base score is 4.2 out of 10.

Auth bypass in Czlonkowski N8n-Mcp

CVE-2026-55608

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.

Vulnerability class: Information Disclosure

Published 2026-07-15 · last modified 2026-07-17.

CVSS v3 metric

CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (19.5th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 19th percentile — 19.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Czlonkowski N8n-Mcp — versions < 2.57.4
N8n-Mcp

Weakness classification (CWE)

References

github.com/czlonkowski/n8n-mcp/security/advisories/GHSA-2cf7-hpwf-47h9 (Mitigation, Vendor Advisory)
github.com/czlonkowski/n8n-mcp/commit/1f42899749ed0c584fb6b4fd63d75233c3edee59 (Patch)
github.com/czlonkowski/n8n-mcp/releases/tag/v2.57.4 (Release Notes)

Frequently asked questions

What is CVE-2026-55608?: CVE-2026-55608 is a medium-severity vulnerability in Czlonkowski N8n-Mcp, classified under Information Disclosure. CVSS score: 4.2/10. Published 2026-07-15.
How severe is CVE-2026-55608?: Medium severity. CVSS v3 base score is 4.2 out of 10.