@angryfirelord
I recomend to spend some time on reading this blog:
http://theinvisiblethings.blogspot.com/
For example
http://theinvisiblethings.blogspot.c...09-slides.html
So, the "Ring -3 Rootkit" presentation is about vPro/AMT chipset compromises.
Unfortunately currently BIOS/UEFI and other forms of firmware example AMT:
1. Are vulnerable to attacks
2. Do a lot of things
3. Have high privileges
This is issue in PC world. Now this could be also in ARMv8 microservers world, because new (not yet published) specification is going to include mandatory ACPI and UEFI, instead of todays simple firmware with device trees. (Yes, these simple firmwares are buggy too and properietary, but there can be written simple, secure open code instead).