>BlackTech actors bypass the router's built-in security features by first installing older legitimate firmware [T1601.002] that they then modify in memory to allow the installation of a modified, unsigned bootloader and modified, unsigned firmware [T1601.001].

I wonder how best to handle this kind of downgrade attack. Is reverting to an older firmware version an intended, supported feature? If so, I assume it's present in case the customer has a problem with the latest firmware and they want to revert. Maybe it makes sense to implement some restrictions on reversions -- e.g. they can only be done with physical access to the device, and it becomes impossible after an upgrade has been in place for 1 month say.

The focus on international subsidiaries was very interesting to me. I wonder what, specifically, it is about a subsidiary that makes it a softer target. Perhaps it's easier to gain physical access to a subsidiary office.