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Re: DNS Attacks
From: Joel jaeggli <joelja () bogus com>
Date: Mon, 20 Feb 2012 13:00:56 -0800

On 2/20/12 09:57 , Christopher Morrow wrote:
On Mon, Feb 20, 2012 at 10:38 AM, Tei <oscar.vives () gmail com> wrote:
I am a mere user, so I all this stuff sounds to me like giberish.

The right solution is to capture the request to these DNS servers, and
send to a custom server with a static message  "warning.html". Nothing
fancy.   With a phone number to "get out of jail", so people can call
to "op-out" of this thing, so can browse the internet to search for a
solution.


in this case, the fbi/dns-changer case, the information is pretty
straightforward for theisp folk... 'client machine makes dns queries
not to the isp dns server (or one of several free dns services), but
to a known bad set of netblocks'

the easy fix is to just stand up (forever, ha!) dns servers on the ip
blocks inside the ISP's network, done and done... 

given the size and distribution of the ip blocks in question I doubt
very much that they will go unused forever...

from a previous message in this thread.

  Quoting the FBI:
  85.255.112.0 through 85.255.127.255
  67.210.0.0 through 67.210.15.255
  93.188.160.0 through 93.188.167.255
  77.67.83.0 through 77.67.83.255
  213.109.64.0 through 213.109.79.255
  64.28.176.0 through 64.28.191.255

which map quite nice to various rir prefix assigments. it's almost like
someone cribbed the whois inetnum field when they loaded their scattergun...

inetnum:         85.255.112.0 - 85.255.127.255

while I have no doubt that some of those prefixes my be run by rather
than simply host to bad actors, if they're returned to rirs, they will
be assigned again, so a static filter policy will return to bite us
again like it always does.

they can then start
notifying the customers via mail/email/carrier-pidgeon that they are
infected, along with instructions about how to get un-infected.

-chris





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