Vulnerability · Published Aug 20, 2026 · Assigned by VulnCheck

CVE-2026-77073n8n before 2.34.1 Cross-Project Credential Access via MCP

Medium 5.3

In plain English

A medium-severity authorization bypass via user-controlled key in n8n from n8n-io. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities).

Severity (CVSS 4.0)5.3Medium

Exploit odds (30 days)0.3%top 71.9% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
n8n-io	n8n	2.34.0 – before 2.34.1
n8n-io	n8n	2.0.0 – before 2.33.4

Weakness: CWE-639 · Vector: 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

References

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