without knowing what your bind server is doing and what the anem they are
looking for it's hard to say..

eg, is it set up to allow normal DNS queries to only a certain range of
client IPs? or is it a private DNS server that's authoritative for an
internal domain that you don't want people external to query?

This could be as simple as someone's laptop set to use your DNS server and
they go home and are suddenly coming from an external IP but still using
your DNS server, so any normal DNS queries are being sent to you first (eg,
www.google.com)

The log itself looks like it's just after an ordinary A record..

If your sure it's an attack it could be someone trying to find names in your
zone by trying a whole bunch of names a'la brute force, but that's pretty
unlikely imho.. by doing that they might be interested in finding internal
IP ranges so they can play NAT tricks for firewall rule enumeration or
perhaps finding the IP of certain functional servers, eg names that indicate
what kind of network service an IP may be providing - eg, samba.example.comor
printserver.example.com - something that gives them a new attack vector..
You could also be participating in a DDoS - because DNS is UDP, forged
source IPs can be used to start sending DNS replies from a whole bunch of
DNS servers to a target IP, thus using all the targets bandwidth

On Wed, Jun 25, 2008 at 3:28 AM, Alex Samad <[EMAIL PROTECTED]> wrote:

> Hi
>
> I have been seeing these in my logs
>
> Jun 25 15:19:45 hufpuf named[3574]: client 59.151.50.248#64821: query
> (cache) './A/IN' denied
> Jun 25 15:19:48 hufpuf named[3574]: client 59.151.50.247#63595: query
> (cache) './A/IN' denied
> Jun 25 15:20:25 hufpuf named[3574]: client 59.151.50.248#10848: query
> (cache) './A/IN' denied
> Jun 25 15:20:28 hufpuf named[3574]: client 59.151.50.247#9753: query
> (cache) './A/IN' denied
>
>
> I can understand 1 / day or maybe / hour, but I have a couple of pages
> full in side an hour.
>
> can somebody shed some light on what they think they can gain ?
>
>
>
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.6 (GNU/Linux)
>
> iD8DBQFIYgG9kZz88chpJ2MRAklTAJ9EglbfqgbT4zr9KBH2FUD9e6Ld3wCg7QVP
> Mh+7tVHJ4dLSPTS4LxvTs0c=
> =Pe1p
> -----END PGP SIGNATURE-----
>
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