CVE-2026-65594 — n8n
CVE-2026-65594 is a CWE-863 vulnerability in n8n. A fix is available for n8n — see the affected versions and patch details below.
n8n before 2.30.1 Missing OAuth Authorization Check
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-65594.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
n8nnpmDescription
Impact
The OAuth 2.1 consent and token-issuance flow introduced in n8n 2.27.0 does not verify that the authenticated user has access to the workflow referenced as the OAuth resource. A member-level user can register an OAuth client, self-approve consent for another user's n8n OAuth2-protected MCP Server Trigger workflow, and obtain a valid token for it.
The workflow runs in the owner's project context with the owner's stored credentials. The attacker sets the tool inputs and reads the outputs, which may include data from the owner's connected integrations, breaking user and project isolation. The resulting executions appear under the owner's account and are not visible to the attacker.
This issue only affects instances running n8n 2.27.0 or later where at least one active workflow uses an MCP Server Trigger node configured with n8n OAuth2 authentication.
Patches
The issue has been fixed in n8n versions 2.29.8 and 2.30.1. Users should upgrade to one of these versions or later to remediate the vulnerability.
Workarounds
If upgrading is not immediately possible, administrators should consider the following temporary mitigations:
- Restrict n8n instance access to fully trusted users only.
- Audit active workflows using the MCP Server Trigger with
n8n OAuth2authentication and consider switching to a different authentication method or deactivating them until the patch is applied.
These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n | ≥ 2.30.0&&< 2.30.1 | 2.30.1npm install n8n@2.30.1 |
| 📦npm | n8n | all versions | 2.29.8npm install n8n@2.29.8 |
Affected Products
n8nn8nDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update n8n to 2.30.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-65594 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is CVE-2026-65594 in your dependencies?
Find it across npm, including transitive dependencies.