Date: Tue, 22 Jul 2008 07:07:26 -1000 From: Clifton Royston <cliftonr@lava.net> To: Doug Barton <dougb@FreeBSD.org> Cc: freebsd-stable@FreeBSD.ORG Subject: Re: FreeBSD 7.1 and BIND exploit Message-ID: <20080722170726.GC1279@lava.net> In-Reply-To: <48860D38.6060209@FreeBSD.org> References: <200807212219.QAA01486@lariat.net> <200807221552.m6MFqgpm009488@lurza.secnetix.de> <20080722160542.GA14592@epia-2.farid-hajji.net> <48860D38.6060209@FreeBSD.org>
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On Tue, Jul 22, 2008 at 09:39:20AM -0700, Doug Barton wrote:
> cpghost wrote:
> >Yes indeed. If I understand all this correctly, it's because the
> >transaction ID that has to be sent back is only 2 bytes long,
>
> 2 bits, 16 bytes.
^^^^ ^^^^^ Think you mean those the other way!
> >and if the query port doesn't change as well with every query, that
> >can be cracked in milliseconds: sending 65536 DNS queries to a
> >constant port is just way too easy! The namespace is way too small,
> >and there's no way to fix this by switching to, say, 4 bytes or
> >even more for the transaction ID without breaking existing
> >resolvers; actually without breaking the protocol itself.
>
> That's more or less accurate, yes.
>
> Doug
I just saw mention in Infoworld - adequate details of the exploit
were guessed by another developer and then confirmed. They're now
circulating, so I think we can expect engineered attacks soon.
All:
Upgrade your servers today, do not wait.
-- Clifton
--
Clifton Royston -- cliftonr@iandicomputing.com / cliftonr@lava.net
President - I and I Computing * http://www.iandicomputing.com/
Custom programming, network design, systems and network consulting services
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