A privilege escalation vulnerability in Authentik Security authentik through 2026.5.6 allows an attacker with a source-scoped SCIM provisioning token to take over any user account including superusers by provisioning a SCIM user that matches an existing local user by username. The SCIM user ingest function adopts pre-existing local accounts by username without validating scope boundaries. An attacker can rewrite or delete any account, including the superuser, using only a limited provisioning credential.

A privilege escalation vulnerability in Authentik Security authentik through 2026.5.6 allows an attacker with a source-scoped SCIM provisioning token to take over any user account including superusers by provisioning a SCIM user that matches an existing local user by username. The SCIM user ingest function adopts pre-existing local accounts by username without validating scope boundaries. An attacker can rewrite or delete any account, including the superuser, using only a limited provisioning credential.