A vulnerability has been identified in SourceCodester Water Billing Management System 1.0 affecting the User Management Endpoint. The issue involves improper authorization in the /classes/Users.php?f=save file processing. This vulnerability allows remote attacks and enables unauthorized access to user management functions. The exploit has been publicly disclosed and is available for use by attackers. The vulnerability appears to allow unauthenticated admin account creation, representing a critical security flaw in the application's access control mechanisms.