PKC

[Pete Bentley]

At Thu, 28 Sep 2000 14:25:24 BST, Ben Laurie writes:
>> > Dave Howe wrote:
>> > > > a) State how the boot sequence on a typical PC would be subverted?
[ much deletia, and I think someone munged the attributions maybe]
>If you run a proper operating system neither the BIOS RAM, nor the boot
>sectors are "trivially writable".

Typical PCs do not run proper operating systems, typically they run
some Windows variant or another (statistically, they're probably
running Windows 9x).

And of course, many supposedly 'proper' operating systems have gaping
holes allowing them to be compromised too (eg in the world of Unix
variants, compromising root leads trivially to compromising of boot
sectors...subverting the BIOS may be harder, but I can't say I'm aware 
of the mechanisms involved... if it's simple port IO, then that should 
be reasonably straightforward).

Pete.