Security Incidents mailing list archives
Re: Pubstro rash
From: Valdis.Kletnieks () vt edu
Date: Fri, 18 Mar 2005 13:40:44 -0500
On Fri, 18 Mar 2005 09:30:51 CST, Joshua Berry said:
I have never had a DNS query that had a response that was over 512 bytes. For that reason I disable all inbound DNS over 53/tcp.
Inquiring minds want to know - how do you *know* you never had a response that was over 512 bytes? :) (Remember - if you have EDNS0 support, you won't notice that the reply was over 512 bytes, and if you don't, it's usually likely that the incomplete response after being truncated to 512 bytes still has enough info to mostly work. Sure, you may only get info on 8 of AOL's farm of MX hosts, and lose the rest because you don't have a TCP connection - but hopefully 1 of those 8 answers anyhow. And if it doesn't, the *next* time you try, AOL will likely hand you a different set of round-robined addresses, and one of the new ones answers. So all you see from the truncation is that things burp for a while).
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Current thread:
- RE: Pubstro rash David Gillett (Mar 17)
- RE: Pubstro rash Nick FitzGerald (Mar 17)
- <Possible follow-ups>
- RE: Pubstro rash k levinson (Mar 17)
- RE: Pubstro rash David LeBlanc (Mar 18)
- Re: Pubstro rash Brian Eckman (Mar 28)
- RE: Pubstro rash Joshua Berry (Mar 18)
- Re: Pubstro rash Jeff Kell (Mar 18)
- Re: Pubstro rash Valdis . Kletnieks (Mar 18)