It is literally just a debug port exposed over the wired HCI interface.
This gives you absolutely nothing at all that you can't get with a normal UART debug port or JTAG. Everything in the HCI commands already exists in the normal bootloader. If you can get a device into bootloader mode, you can peek and poke flash and memory, along with everything else.
There is absolutely nothing here.
You can create malicious firmware, sure, but it has nothing to do with this HCI thing.
It is literally just a debug port exposed over the wired HCI interface.
This gives you absolutely nothing at all that you can't get with a normal UART debug port or JTAG. Everything in the HCI commands already exists in the normal bootloader. If you can get a device into bootloader mode, you can peek and poke flash and memory, along with everything else.
There is absolutely nothing here.
You can create malicious firmware, sure, but it has nothing to do with this HCI thing.