Proof of universal backdoor in Intel-CPU available?

As
soon as i know there are many speculations about a universal backdoor
in the Intel Processor.

I'm not an expert in such things, but If so, then some kind of
Remote-SSH has to be enabled at the bios / cpu, in order to bypass
router firewalls, wich will try to contact a server in the internet from
time to time.

And if so, then it might be tested via network-spoofing that there is
such an action.

Does anyone know about such an investigation have been done?