CVE-2026-65014: n8n before 2.28.0 Authentication Bypass via test-webhook

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-22 · updated 2026-10-29
Weakness: CWE-306

Description

n8n before 2.28.0 (and before 2.27.4 on the 2.27.x branch) registers the DELETE /${restEndpoint}/test-webhook/:id endpoint before authentication middleware is applied, allowing any unauthenticated network caller who knows a workflow ID to cancel that workflow's active test webhook registration. The impact is limited to disrupting in-progress test sessions; production webhooks, persistent workflow state, and stored data are not affected.

Affected products

n8n-io n8n: from 2.27.0 before 2.27.4 — fixed in 2.27.4
n8n-io n8n: before 2.27.4 — fixed in 2.27.4

How to fix

Upgrade to a fixed version: n8n-io n8n 2.27.4; n8n-io n8n 2.27.4. Check the vendor advisory for mitigations.

References

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