Harbor allows privilege escalation from zero to admin vulnerability.
core/api/user.go in Harbor 1.7.0 through 1.8.2 allows non-admin users to create admin accounts via the POST /api/users API, when Harbor is setup with DB as authentication backend and allow user to do self-registration. Fixed version: v1.7.6 v1.8.3. v.1.9.0. Workaround without applying the fix: configure Harbor to use non-DB authentication backend such as LDAP.
You have to update to latest version.