phpMyFAQ - Privilege Escalation via Missing SuperAdmin Guard in user/add Endpoint

phpMyFAQ before 4.1.5 contains a privilege escalation vulnerability in the user/add API endpoint that allows non-SuperAdmin administrators to create SuperAdmin accounts. A delegated administrator with USER_ADD/EDIT/DELETE permissions can call POST /admin/api/user/add with isSuperAdmin: true and attacker-chosen credentials to create a SuperAdmin account, then authenticate as that account to achieve full instance takeover.