Hardcoded credentials

A vulnerability has been identified in CP-8000 MASTER MODULE WITH I/O -25/+70°C (All versions < V16.20), CP-8000 MASTER MODULE WITH I/O -40/+70°C (All versions < V16.20), CP-8021 MASTER MODULE (All versions < V16.20), CP-8022 MASTER MODULE WITH GPRS (All versions < V16.20). An undocumented debug port uses hard-coded default credentials. If this port is enabled by a privileged user, an attacker aware of the credentials could access an administrative debug shell on the affected device.