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Re: Tightened DNS security question re: DNS amplification attacks.
From: Steve Pirk <orion () pirk com>
Date: Tue, 27 Jan 2009 17:49:05 -0800 (PST)

On Wed, 28 Jan 2009, jay () miscreant org wrote:

Quoting John Martinez <jmartinez () zero11 com>:

Are we still seeing DNS DDoS attack?

Yep. I'm seeing ~2 queries/sec targetting

Also seeing requests from every 1 minute 2 seconds.

I run a small personal nameserver and even I am seeing requests for that address at ~1/sec.

How many people have upgraded to the latest version of Bind 9? Reason
I ask is that when I do my nightly port scan of my server, I no longer see named listening to udp on a random high order port (for replies I believe?). Almost the next day, I started hearing about/seeing these DNS attacks.

Previous nmap scan showed:
53/tcp    open          domain
53/udp    open|filtered domain
33591/udp open|filtered unknown

Now nmap shows:
53/tcp    open          domain
53/udp    open|filtered domain

The listen port (> 32767 I believe) is no longer there with BIND 9.4.3-P1.
The port was bound at startup time and did not change as long as named was still running.
Equal bytes for women.

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