Re: recursive DNS servers DDoS as a growing DDoS problem

[Gadi Evron <ge@xxxxxxxxxxxx>]

MaddHatter wrote:
> > We discussed recursive DNS servers before (servers which allow to query
> > anything - including what they are not authoritative for, through them).
> > ...
> > One of the problems is obviously the spoofing. ...
>
>
> Maybe I'm misunderstanding the problem here (but I don't think so). It
> seems to be the issue is not DNS -- recursive or not, but rather a failure
> to adhere to BCP 38.
>         http://rfc.net/bcp38.html
>
> One may get easier/larger amplification from a recursive DNS server,
> but the same problem exists for a non-recursive server. DNS, then, isn't
> really where the problem needs to be fixed.

You are right, to a degree.

Spoofing is indeed the attack vector and it can also be utilized for 
NTP, ICMP, etc. It is to blame.

Still, DNS is what's being exploited and in my opinion a broken feature 
being exploited needs fixing, or it will be exploited.