I feel like this article reflects some significant technical confusion. The BMC is supposed to be on a trusted network inaccessible from the outside. I've always viewed authentication on the BMC as being like the numeric lock on luggage--it's designed to keep honest people honest, not for real security. Being able to bypass the BMC security is really not a big deal. What the Bloomberg article says about the hardware exploit is much worse:

> > The rogue instructions, Bloomberg reported, caused the BMCs to download malicious code from attacker-controlled computers and have it executed by the server’s operating system.

It's using the fact that the BMC has unfettered access to the rest of the machine to compromise the code running on the server itself. That's valuable even if the BMC itself is on a private network inaccessible to the attacker.