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Intel CPUs have an embedded supervisory CPU called the Management Engine. It can read all of memory, control power states on the main CPU, and generally has sup
by dsr_ 9y ago
Intel CPUs have an embedded supervisory CPU called the Management Engine. It can read all of memory, control power states on the main CPU, and generally has super-root privileges on everything. You, an end-user, aren't allowed to program it. The current MEs run a form of Minix. They represent an incredible security and privacy risk, because we don't know what code they run and it is widely believed that the NSA or other intelligence agencies have backdoor access. Remote backdoor access, even: the ME can talk to the network.
A JTAG is a standard minimal serial port used for debugging purposes. You'll find them on nearly all embedded devices - routers, phones, TVs, refrigerator controllers... usually appearing as a set of two or three contact points. Sometimes they connect directly to a debugger.
In this case, it appears that at least some Intel CPUs have a JTAG on the ME that can be routed through the on-CPU USB handler, and thus physical access to the right USB ports can be used to access the ME.
- metalliqaz 9y agoAlso that since they have JTAG debugging access, they have unrestricted access to the normally hidden processor, meaning they can disassemble it, peer into memory, and probably find a method of permanently disabling the ME.
- kevin_b_er 9y agoAnd if they can access it without hardware modifications it means any USB device has super-root access to the machine. And then it would mean you can't block it unless you don't connect USB device. I suspect they fiddled with something to get access, however. Attached something to motherboard or similar.
- kinleyd 9y agoThank you for that great explanation.
- quickben 9y agoTo add, and maybe the others can correct me if I'm wrong: Intel ME can be controlled remotely if you have an Intel lan card, even if the main cpu is off, but the motherboard is powered on. It goes from there and gets worse is my understanding.
- cmh1729 9y agoIs it known/suspected that AMD have an equivalent?
- stryan 9y agoYes, the AMD PSP[1] chip. [1]: http://www.amd.com/en-us/innovations/software-technologies/security http://www.amd.com/en-us/innovations/software-technologies/s...
- Hupriene 9y agoAMD Platform Security Processor
- mkesper 9y agoYes they do: https://www.reddit.com/r/security/comments/4ot223/do_amdprocessors_have_something_like_intel/ https://www.reddit.com/r/security/comments/4ot223/do_amdproc...
- retrac98 9y agoThis is great (and horrifying), thank you!