I'm getting ridiculously pissed off at Intel's Management Engine (etc.), yet again. I'm learning new terrifying things it does, and about more exploits. Anything this nefarious and overreaching and untouchable is evil by its very nature.

(tl;dr at the bottom.)

I also learned that -- as I suspected -- AMD has their own version of the bloody thing. Apparently theirs is a bit less scary than Intel's since you can ostensibly disable it, but i don't believe that because spy agencies exist and people are power-hungry and corrupt as hell when they get it.

For those who don't know what the IME is, it's hardware godmode. It's a black box running obfuscated code on a coprocessor that's built into Intel cpus (all Intell cpus from 2008 on). It runs code continuously, even when the system is in S3 mode or powered off. As long as the psu is supplying current, it's running. It has its own mac and IP address, transmits out-of-band (so the OS can't see its traffic), some chips can even communicate via 3g, and it can accept remote commands, too. It has complete and unfettered access to everything, completely invisible to the OS. It can turn your computer on or off, use all hardware, access and change all data in ram and storage, etc. And all of this is completely transparent: when the IME interrupts, the cpu stores its state, pauses, runs the SMM (system management mode) code, restores the state, and resumes normal operation. Its memory always returns 0xff when read by the os, and all writes fail. So everything about it is completely hidden from the OS, though the OS can trigger the IME/SMM to run various functions through interrupts, too. But this system is also required for the CPU to even function, so killing it bricks your CPU. Which, ofc, you can do via exploits. Or install ring-2 keyloggers. or do fucking anything else you want to.

tl;dr IME is a hardware godmode, and if someone compromises this (and there have been many exploits), their code runs at ring-2 permissions (above kernel (0), above hypervisor (-1)). They can do anything and everything on/to your system, completely invisibly, and can even install persistent malware that lives inside your bloody cpu. And guess who has keys for this? Go on, guess. you're probably right. Are they completely trustworthy? No? You're probably right again.

There is absolutely no reason for this sort of thing to exist, and its existence can only makes things worse. It enables spying of literally all kinds, it enables cpu-resident malware, bricking your physical cpu, reading/modifying anything anywhere, taking control of your hardware, etc. Literal godmode. and some of it cannot be patched, meaning more than a few exploits require replacing your cpu to protect against.

And why does this exist?
Ostensibly to allow sysadmins to remote-manage fleets of computers, which it does. But it allows fucking everything else, too. and keys to it exist. and people are absolutely not trustworthy. especially those in power -- who are most likely to have access to said keys.

The only reason this exists is because fucking power-hungry doucherockets exist.