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

Paul Wouters <paul@cypherpunks.ca> Fri, 07 March 2014 09:00 UTC

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From: Paul Wouters <paul@cypherpunks.ca>
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To: Dan York <york@isoc.org>
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Subject: Re: [DNSOP] DNS privacy and Team Cymru's report on 300, 000 SOHO routers with compromised DNS settings
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On Thu, 6 Mar 2014, Dan York wrote:

> 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.

Run a local resolver and reconfigure it automatically (eg using
dnssec-trigger and friends) to use the DHCP obtained DNS servers
only as forwarders.

>  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).

If the domains were signed, even if you used the rogue DNS as forwarder,
you would at least notice you are under attack.

Paul