An issue was discovered on Enphase Envoy R3.x and D4.x devices with v3 software. The default admin password is set to the last 6 digits of the serial number. The serial number can be retrieved by an unauthenticated user at /info.xml.

An issue was discovered on Enphase Envoy R3.x and D4.x (and other current) devices. The upgradestart function in /installer/upgradestart allows remote authenticated users to execute arbitrary commands via the force parameter.

An issue was discovered on Enphase Envoy R3.x and D4.x devices. There is a custom PAM module for user authentication that circumvents traditional user authentication. This module uses a password derived from the MD5 hash of the username and serial number. The serial number can be retrieved by an unauthenticated user at /info.xml. Attempts to change the user password via passwd or other tools have no effect.

An issue was discovered on Enphase Envoy R3.x and D4.x devices. There are hardcoded web-panel login passwords for the installer and Enphase accounts. The passwords for these accounts are hardcoded values derived from the MD5 hash of the username and serial number mixed with some static strings. The serial number can be retrieved by an unauthenticated user at /info.xml. These passwords can be easily calculated by an attacker; users are unable to change these passwords.