Undocumented access path in mH-DEVELOPER

mH-DEVELOPER smart home module contains a hardcoded SSH public key in /root/.ssh/authorized_keys, serving as a potential backdoor. The SSH daemon allows root login via key authentication and starts automatically. An attacker with the matching private key can gain a root shell on any affected device, resulting in full system compromise. The key cannot be removed without remounting the file system and survives a factory reset. Vendor notes that this functionality was used only for service purposes. This issue was fixed in version 3.0.30