> On Thu, 19 Nov 1998, John Fulmer wrote:
>
> > EGADS! Is there NO security on the processor microcode? Could this be
> > exploited to do evil narsty things?
>
> Yeah. #1 Exploit: Resurrect the F00F bug. #2 Exploit: Infamous Pentium
> floating point bug. The list is endless.
Those are only DOS attacks, think of what could be done if the microcode
was changed so that memory and IO protection bits are suddendly ignored...
a malicious program can now access any memory or IO unhindered by any
protection mechanisms.
I assume the CPU only accepts microcode programming from security ring 0.
Thus, no user space program (on a decent OS) could reprogram the CPU.
Anyone know how this programming works? Is Intel keeping it a secret?
Cheers,
Rafael
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