Re: ISS Security Advisory: Multiple Remote Vulnerabilities in BIND4 and BIND8 (fwd)]

From: Matt Piechota (piechota@argolis.org)
Date: 11/13/02


Date: Tue, 12 Nov 2002 19:10:32 -0500 (EST)
From: Matt Piechota <piechota@argolis.org>
To: Michael Carew <MichaelCarew@bytecraftsystems.com>

On Wed, 13 Nov 2002, Michael Carew wrote:

> At least limiting it prevents someone setting up an authoritative server,
> then making a query to that domain off your name server.
>
> They are then reliant on a legitimate client querying the server with the
> malicious content, rather than them doing it themselves.
>
> Reducing the changes substantially I would imagine.

Not as much as you'd think. If you use tcpwrappers and something like
*.foo.edu, it'll do a reverse lookup to find out if a.b.c.d matches
*.foo.edu. I think other things do at least reverse lookups as well (ie,
so 'w' show what host I'm connecting from vs what IP).

It's a little more difficult to have a reverse DNS domain, but not much.
Besides, I think there's a few services that do a reverse then a forward
to see if the names match. (I think I remember reading that)

-- 
Matt Piechota
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