CVE-2021-28152
Hongdian H8922 3.0.5 devices have an undocumented feature that allows access to a shell as a superuser. To connect, the telnet service is used on port 5188 with the default credentials of root:superzxmn.
Date published : 2021-05-06
http://en.hongdian.com/Products/Details/H8922