
A CPU bug with undocumented opcodes, possibly Intel (scroll to p. 155) - baybal2
https://www.blackhat.com/docs/us-17/thursday/us-17-Domas-Breaking-The-x86-ISA.pdf
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ohaal
Related talk (relevant part starts at 38:43)
[https://www.youtube.com/watch?v=KrksBdWcZgQ](https://www.youtube.com/watch?v=KrksBdWcZgQ)

Quote from the talk: _I don 't want to make it sound like the sky is falling.
This was found on one very esoteric processor that is not used in widespread
production. I think it's mostly interesting from an academic perspective that
we have a tool that is able to find these kinds of things now._

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baybal2
Sorry for the typo, it is p. 155.

For quite a few days, people were suspecting that to be an Intel bug. The
desktop shown in the video was a Dell Precision one, which means Core or a
Xeon.

Another suspected cpu is said to be Intel X1000, if the demo was not running
on the desktop. This was because Intel has issued a non-public errata just for
major embedded partners before.

From myself, I will add that another suspect is Intel 80579 which is a still
sold Pentium M/Core 1 SoC

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dschuetz
While the title is a bit misleading, the presentation suggests enough to say
that common CPU designs and architectures should be revised. _Undocumented_
alone should always raise red flags. Imagine your average safe or door lock
has _undocumented_ keys or means to be opened without you noticing. Or your
car having _undocumented_ extras.

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phoe-krk
Page 154 says nothing about Intel. Kindly stop feeding the FUD.

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eleitl
It's page 155 and they've blanked out the vendor.

The bar is too short for Transmeta and too broad for AMD. It could well be
Intel, judging from their other slide using Intel in the same location and
font.

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contrarian_
The bar is just the right width for "(redacted)", I wouldn't read into it.

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saas_co_de
It looks like it says a Transmeta bug ... wtf is that? who cares?

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contrarian_
One page later: (redacted) hardware bugs.

Sounds like something that would be hopefully fixable in microcode.

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seba_dos1
If it's really about Intel here, at least this seems like something that could
be mitigated with microcode update.

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wolfgke
Assuming that you mean page 155: What is your evidence that it is a bug on
Intel Core?

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FLUX-YOU
This is misleading. The author of the talk has not revealed the vendor.

