Auth bypass in N8n
CVE-2026-77081
n8n before 1.123.69, 2.x before 2.33.4, and 2.x before 2.34.1 contain an allowed-domains bypass in the GraphQL node. When the node's Authentication parameter is set to expression mode, every authentication-gated credential selector is treated as active; if two credentials of different types are attached, the node enforces the allowed-domains policy of only the first credential while still attaching material from both. An authenticated user with workflow-authoring rights can thereby send a domain-restricted credential to an attacker-controlled endpoint, exfiltrating it with the leaked credential's permissions.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (29.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 29.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.002
Affected products
- N8n — versions 2.34.0
- N8n-Io N8n
Weakness classification (CWE)
References
- github.com/n8n-io/n8n/security/advisories/GHSA-wcv8-x773-j96r (vendor-advisory, Mitigation, Vendor Advisory)
- www.vulncheck.com/advisories/n8n-before-allowed-domains-bypass-via-graphql-node (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-77081?
- CVE-2026-77081 is a high-severity vulnerability in N8n, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 7.1/10. Published 2026-08-20.
- How severe is CVE-2026-77081?
- High severity. CVSS v3 base score is 7.1 out of 10.