Re: No shell => secure?

[Valdis.Kletnieks () vt edu]

On Fri, 09 Jul 2004 22:41:59 +0200, Matthias Benkmann <matthias () winterdrache de>  said:

> So I have one example to back up my claim. Now it's your turn. Give me a
> worm that my scheme would not have protected me against. That's all you
> need to do to convince me. Easy, isn't it? No need to give me lengthy
> lectures. Just give me one URL. If you can't do that, don't bother
> replying. You're wasting your time, because you're telling me things I
> already know.

Any worm that doesn't invoke execve() won't be slowed down in the slightest
by your scheme.  The only reason why there aren't many examples of that
is because nobody feels like beating their heads against the wall re-inventing
the wheel when execve("/bin/sh") will do the work for you.

Yes, your scheme *will* provide security.  The problem is that usually,
people want something resembling *usability* too.  And your scheme would
totally fail on that.

Most notably, the *real* reason why Slapper wouldn't hit a machine modified
as you suggest isn't because /bin/sh wasn't there, but because Apache
wouldn't run in such an environment...  Ponder that for a while...

But of course you already know that....

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