
Intel’s SGX coughs up crypto keys when scientists tweak CPU voltage - pwg
https://arstechnica.com/information-technology/2019/12/scientists-pluck-crypto-keys-from-intels-sgx-by-tweaking-cpu-voltage/
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exikyut
Suggestion: change the URL to
[https://www.plundervolt.com](https://www.plundervolt.com), which more
immediately offers a technical overview of the situation. The Ars Technica
article is more editorial.

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dang
[https://news.ycombinator.com/item?id=21759683](https://news.ycombinator.com/item?id=21759683)

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winrid
How likely is changing the voltages to lock up the system vs the attack
actually working?

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joezydeco
I've worked with some secure enclave chips that go into tamper mode (self-
erasing of keys, hard fault, etc) when the voltage deviates outside a certain
range.

But this chip seems to have programmable voltage changes. Seems like you could
prevent crypto access unless the registers were all in spec.

~~~
jdsully
Chip power networks are very complicated RC circuits. By modulating both the
workload and the voltage it should be possible to create localized brownouts
only in portions of the chip. This would bypass normal voltage monitoring.
This sort of thing is already a huge problem in chip design today without the
adversarial component complicating it further.

It does make the attack much more difficult though.

