[DoctorOetker]

I never claimed remote updating would prevent supply chain attacks.

I was responding to:

> With a hardware switch, none of that malware will survive a reboot of the device.

A reboot of the inverter would not prevent a supply chain attack using MPPT measurement electronics for an optical backdoor channel.

[WalterBright]

So don't put the backdoor channel in without a physical switch.

[DoctorOetker]

Attackers don't ask permission.

The hardware backdoor channel is present anyway because MPPT needs it.

The software can abuse the measurements to listen for optically transmitted commands.