n8n before 2.35.4 and 2.36.x before 2.36.2 does not validate credential references in the inline workflow JSON of nodes that execute an inline sub-workflow (e.g., the Workflow Tool node). A shared-workflow editor, or any user creating/updating a workflow via the REST API, Public API, or MCP, can persist a node referencing a credential they do not own. When the workflow is later executed under an identity that holds the credential, the inline sub-workflow resolves the secret and can send it to an attacker-controlled endpoint, resulting in credential exfiltration.
CVE-2026-85166
CVSS base score
6.5 (v3.1)
Severity
MEDIUM
Attack vector
Network
Weakness
CWE-863
Last modified
October 29, 2026
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected products
n8n n8n
References
- github.com Mitigation, Vendor Advisory
- www.vulncheck.com Third Party Advisory