n8n versions prior to 1.123.64, 2.29.8, and 2.30.1 contain a privilege escalation vulnerability in the Enterprise SSO instance-role provisioning feature. The provisioning path maps an IdP-asserted role claim to an n8n global role but does not restrict assignment of the global:owner role, unlike the token-exchange identity path which rejects such assignments. If an attacker controls the instance-role claim value issued by the IdP and instance-role provisioning is enabled via the N8N_SSO_SCOPES_PROVISION_INSTANCE_ROLE environment variable (disabled by default), they can be provisioned as an instance owner. This grants them full administrative privileges over workflows, credentials, users, and instance configuration within n8n.

An attacker who can manipulate the instance-role claim in an Enterprise SSO setup with instance-role provisioning enabled can escalate their privileges to global owner. This results in full administrative control over the n8n instance, including workflows, credentials, users, and configuration, potentially leading to complete compromise of the system.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Mitigation requires disabling instance-role provisioning by ensuring the N8N_SSO_SCOPES_PROVISION_INSTANCE_ROLE environment variable remains disabled (default setting) or applying any official patches once available. Until then, restrict control over IdP-issued instance-role claims to trusted sources only.