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

EPSS: 0.003 (20.1th percentile) — read the EPSS interpretation.

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.

Affected products

Czlonkowski N8n-mcp — versions < 2.57.4
N8n-mcp

Weakness classification (CWE)

References

security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)
security-advisories@github.com (x_refsource_MISC, 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.