Yes, but also this.  (expanded from "feel")

It may also make Kaminsky style attacks easier if an attacker can blind an auth 
server from handing out responses.  If the counter values are real from the RFC 
style paper, every other response becomes a truncated reply in a flood 
situation.  This will extend the attack window by  the time it takes to 
establish a TCP connection and query, or to the time it takes to retransmit the 
query plus TCP handshake if the blinding is successful.  This assumes the 
second query works.  But in reality it has the same chance as the first.

Assuming about 100ms for TCP handshake and two seconds for timeout and retry 
followed by the TCP handshake, This means the window for potential false 
responses moves to about 1100ms on average. 

If a UDP reply would normally make it to the server in 100 ms, this opens a 
window 11 times as wide.

This simple math only accounts for one server, however.  Someone with better 
probabilistic skills than I have, at 1:30am, should do the math with more than 
one server, and include the attack probably as well.

--Michael

On Jun 28, 2012, at 1:15, pangj <[email protected]> wrote:

> 
>> Even with the slip values, I still feel this can open a wider window for 
>> other forms of attacks against a DNS zone.
> 
> For example, the attacker spools with a legetimate IP and make a number of 
> queries, thus RRL blocks that legetimate IP by mistake?
> 
> -- 
> Email/Jabber/Gtalk: [email protected]
> Free DNS Hosting with www.DNSbed.com
> 
> 
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