Potentially dangerous Pentium bug disc

Wed Nov 12 15:42:30 UTC 1997

On Tue, 11 Nov 1997, Jay R. Ashworth wrote:

> Date: 09 Nov 1997 09:26:39 +0100
> From: Torsten Hilbrich <Torsten.Hilbrich at bln.de>
> Subject: New Pentium flaw
> 
> Yesterday (Nov, 8) I found the following information on the news-ticker
> page of the German Heise-Verlag (shortened to the essential information):
> 
> > The Pentium in standard and MMX version halts on execution of the
> > instruction:
> >    F0 0F C7 C8
> > This code sequence works independent of any memory protection of the
> > operating system.
> 
> I was able to reproduce this bug on a Pentium 133 system with the following
> operating systems: DOS, Windows 95, Linux 2.0.31, and FreeBSD 2.2.x.
> 
> I don't know about PentiumPro and Pentium II.
> 
> The risk?  Every pentium based server with user access for executing
> programs can be crashed using this code sequence.  Not to mention Trojan
> Horses or Active-X controls.


	Does anybody know if this affects the Cyrix and AMD "Pentium
Clone" chips?