I'm sure states have an interest in these backdoors but I don't know of evidnece they're directly involved with it yet. It would be a natural fit as you say of

I'm sure states have an interest in these backdoors but I don't know of evidnece they're directly involved with it yet. It would be a natural fit as you say of course. > Technically yes, you were right, there is a chance for us to intercept the communication between PCH and the Intel CPU then reverse engineer the protocol or even directly RE the PCH chip and create a substitute. But how practical, I don't really know. Firstly, the effort required is beyond most people can afford IMO. Put those cost/effort etc. aside, there might some undocumented CPU features actually need ME to work and if I were the designer, I would at least use signed if not encrypted payload, then make the RE process much less likely. Well, yes, but I see this more as a project that would show up at DEFCON as a hack or maybe something commissioned by System76, Purism, Raptor, Pine or one of these companies.