[DNSOP] DNS privacy and Team Cymru's report on 300, 000 SOHO routers with compromised DNS settings

Dan York <york@isoc.org> Thu, 06 March 2014 23:09 UTC

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From: Dan York <york@isoc.org>
To: "dnsop@ietf.org" <dnsop@ietf.org>
Thread-Topic: DNS privacy and Team Cymru's report on 300, 000 SOHO routers with compromised DNS settings
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Date: Thu, 6 Mar 2014 23:09:33 +0000
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Subject: [DNSOP] DNS privacy and Team Cymru's report on 300, 000 SOHO routers with compromised DNS settings
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DNSOP members,

Given our session today talking about protecting DNS privacy, I found an interesting bit of synchronicity upon going back to my room and seeing this article in my feeds about a compromise of at least 300,000 small office / home office (SOHO) home routers  by a variety of attacks in which their DNS server values were changed and consumers were redirected to other pages as a result:

(and http://www.circleid.com/posts/20140305_dynamic_dns_customers_check_your_router_settings/ )

The actual report from Team Cymru was announced just this past Monday - https://twitter.com/teamcymru/status/440488571666198528  and is available at:


Now, in this case the attackers compromised the local network devices and took over control of the local recursive resolvers.  In this case of the attacker controlling the recursive resolver, I don't know that any of the various solutions thrown around today would do anything to help with this.  I don't even see DNSSEC helping much here, either, given that the attacker could just strip out the DNSSEC info (unless, perhaps, the home computers were running full (vs stub) recursive resolvers that also did DNSSEC-validation).

I just thought it was an interesting example of a type of attack against DNS that is out there now.


Dan York
Senior Content Strategist, Internet Society
york@isoc.org <mailto:york@isoc.org>   +1-802-735-1624
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