Executive brief
n8n is a workflow automation platform that allows users to create and manage automated processes. A flaw in its shared-workflow feature allows an editor with access to a shared workflow to reference credentials they don't have permission to use by embedding them in a sub-workflow definition, potentially allowing them to steal sensitive credentials. This bypasses access controls and requires the attacker to know the credential ID and have editor access to a shared workflow.
Technical details
The vulnerability is an authorization bypass (CWE-863) in n8n's credential-access validation logic. The Execute Sub-workflow node accepts inline workflow JSON, but the credential checks only validated top-level node credentials, not those referenced inside the inline JSON parameter. An authenticated user with Editor access to a shared workflow can craft an inline sub-workflow JSON that references a credential they do not have direct access to; this passes both save-time and runtime validation because it resolves in the parent workflow's project context. The attacker can then use or exfiltrate the credential. Exploitation requires: (1) workflow sharing enabled, (2) explicit Editor access grant, and (3) knowledge of the target credential ID. Patches are available in n8n 1.123.67, 2.31.5, and 2.32.1.
Affected products
- n8n n8n < 1.123.67, >= 2.0.0-rc.0 and < 2.31.5, >= 2.32.0 and < 2.32.1
Timeline
- 2026-07-22: disclosed