CVE-2026-77073

n8n before 2.34.1 Cross-Project Credential Access via MCP

State: Published
Severity: 5.3 Medium
Published: Aug 20, 2026
Updated: Aug 25, 2026
Reserved: Aug 20, 2026

Description

n8n versions before 2.34.1 contain a credential validation bypass in the MCP create_workflow_from_code tool when authentication type is set to an expression. Attackers with a valid MCP Bearer API key and knowledge of a target credential ID can persist unauthorized cross-project credential references on workflows in different projects.

Scores

CVSS	Score	Vector	Source
4.0	5.3 Medium	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N	VulnCheck

Weaknesses

CWE-639 Authorization Bypass Through User-Controlled Key

Affected Products

Product	Versions
n8nn8n-io	2.34.0 to before 2.34.1Affected 2.34.1Not affected
n8nn8n-io	2.0.0 to before 2.33.4Affected 2.33.4Not affected

References

GitHub Security Advisory (GHSA-vfrj-582q-mvcp)vendor-advisory
VulnCheck Advisory: n8n before 2.34.1 Cross-Project Credential Access via MCPthird-party-advisory

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.