PRTG Network Monitor before 18.2.40.1683 allows an authenticated user with a read-only account to create another user with a read-write acc…

PRTG Network Monitor before 18.2.40.1683 allows an authenticated user with a read-only account to create another user with a read-write account (including administrator) via an HTTP request because /api/addusers doesn't check, or doesn't properly check, user rights.