Re: [patch] Add basic sanity checks to the syscall execution patch

On Sat 2008-09-06 17:45:51, Ingo Molnar wrote:
> 
> * Willy Tarreau <w@1wt.eu> wrote:
> 
> > Then they will simply proceed like this :
> >   - patch /boot/vmlinuz
> >   - sync
> >   - crash system
> > 
> > => user says "oh crap" and presses the reset button. Patched kernel boots.
> >    Game over. Patching vmlinuz for known targetted distros is even easier
> >    because the attacker just has to embed binary changes for the most
> >    common distro kernels.
> 
> a reboot often raises attention. But yes, in terms of end user boxes, 
> probably not. Anyway, my points were about transparent rootkits 
> installed on a running system without anyone noticing - obviously if the 
> attacker can modify the kernel image and the user does not mind a reboot 
> it's game over.

Well, install a rootkit in /boot/vmlinuz, sync, then wait for user to
reboot its system?

Even well-kept servers are rebooted from time to time.

I agree -- the only way to win is not to play this game.

-- 
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