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

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.