n8n: Instance AI Credential Setup Accepts Unvalidated Probe URL from Fetched Content

MediumCVE-2026-86074 · Published Sep 10, 2026

## Impact Instance AI credential setup accepted a credential test/verification URL without checking it matched the workflow node's origin. Exfiltration required the user to actively inject an attacker-controlled URL into the setup flow. The patch derives the credential destination from the node's own URL and confines authenticated requests, redirects and probes to that origin. ## Patches The issue has been fixed in n8n versions 2.38.2 and 2.37.7. 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: - Disable the Instance AI module by removing `instance-ai` from the `N8N_ENABLED_MODULES` environment variable if it is not required. - Restrict n8n instance access to fully trusted users only. - Rotate any third-party API credentials that were set up using the Instance AI credential-setup flow on affected versions. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.