CVE-2021-28152: Hongdian h8922 Firmware

Critical severity, CVSS 9.8. EPSS: 5.2% chance of exploitation in the next 30 days.

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.

Affected products

• Hongdian h8922 Firmware: version 3.0.5 only

Published 2021-05-06. Last modified 2026-06-17.