Bugtraq mailing list archives
Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem
From: Security Lists <securitylists () uniontown com>
Date: Wed, 08 Mar 2006 13:46:19 -0500
Sorry, I don't see this as amplification in your example, because YOUR dns servers are 100% of the traffic. 1:1 ratio.
Now, if you get the world to cache your text records, and have THEM flood with source-spoofed UDP (unrelated to the victim's DNS servers), that'd work, and is actually a good example of amplification. There's plenty of open DNS servers out there that'll do this, but each one of them is going to hit your local dns server initially.
-Mark Coleman Geo. wrote:
In the scenario you describe, I cannot see any actual amplification...I'll give you a senario where you can see. lets say you have 2 name servers that are local to you. I setup a domain, example.com. In this domain I create a text record which is 100K in length, I don't know, perhaps I paste the source code to decss in it, whatever it's a big text record. Now I simply spoof a UDP packet using your IP address as the source address and send it to both of your dns servers. This packet is a query for the example.com text record. I have now sent two very small packets and you have received 200K of traffic. That's the amplification, one small udp packet, one large text record in return. Note, I don't have to use your local servers, but this way it makes it more fun to troubleshoot because it looks like you are the cause of your own flooding.. Geo. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
Current thread:
- RE: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Geo. (Mar 10)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Security Lists (Mar 10)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem gboyce (Mar 10)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Mark Senior (Mar 10)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Robert Story (Mar 17)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Bram Matthys (Syzop) (Mar 20)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Tim (Mar 23)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem gboyce (Mar 10)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Security Lists (Mar 10)
- Re: [Full-disclosure] Re: recursive DNS servers DDoS as a growing DDoSproblem Måns Nilsson (Mar 17)