
Reverse Engineering X86 Processor Microcode - unmole
https://www.usenix.org/conference/usenixsecurity17/technical-sessions/presentation/koppe
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jsnell
[https://news.ycombinator.com/item?id=15035408](https://news.ycombinator.com/item?id=15035408)

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d33
I only skimmed through, but... was there no crypto that needed to be broken in
order to hack microcode?

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zkms
From the paper

> Our analysis focuses on the AMD K8/K10 microarchitecture since these CPUs do
> not use cryptographic signatures to verify the integrity and authenticity of
> microcode updates. Note that Intel started to cryptographically sign
> microcode updates in 1995 [15] and AMD started to deploy strong
> cryptographic protection in 2011 [15]. We assume that the underlying
> microcode update mechanism is similar, but cannot analyze the microcode
> updates since we cannot decrypt them.

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d33
So basically they found a way to change microcode in ten-year-old
processors... though, it's still impressive.

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pjmlp
Given the current state of PC market, there are plenty of those processors
around.

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_pmf_
It's very inspiring that the systems responsible for running civilization are
corporate secrets.

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orclev
Inspiring isn't exactly the word I would choose.

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gpvos
It does convey about the intended amount of sarcasm though.

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phkahler
This seems like a really complex addition to the hardware. My first thought
was that when process scaling fails and IF instruction sets stabilize more,
they may be able to remove this flexibility and gain some power/area/speed
benefits. My second thought was - maybe Intel already does that when a CPU has
been out a while, they could bake the microcode more firmly into gates after
it's been out a while.

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hidiegomariani
impressive

