GHSA-cj9h-qx8g-pq2g: n8n: Shared-Workflow Editor Can Exfiltrate Credentials via Inline Sub-Workflow JSON

n8n’s credential-access checks validated only a node’s top-level credentials, not credentials referenced inside an Execute Sub-workflow node’s inline workflow JSON. A member with editor access to a shared workflow could reference a credential they were not permitted to use inside that inline JSON; it passed both save-time and runtime validation and resolved in the parent workflow’s project context, letting the member use or exfiltrate a credential they could not otherwise access.

Exploitation requires workflow sharing to be enabled and the attacker to have been explicitly granted Editor access to a shared workflow. The attacker must also know the target credential’s ID.