Re: [Trans] DNSSEC also needs CT

Joseph Bonneau <> Mon, 12 May 2014 17:55 UTC

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From: Joseph Bonneau <>
Date: Mon, 12 May 2014 13:54:41 -0400
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To: Nico Williams <>
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Cc: Warren Kumari <>, "" <>, Paul Wouters <>, Ben Laurie <>
Subject: Re: [Trans] DNSSEC also needs CT
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> Clients (lazily perhaps).  The public.  Domain owners.  Registrars.

Certainly possible, but I wonder how much this will happen in a world of
thousands of DNSSEC-CT logs existing for various domains. Some of them will
inevitably screw up. Will it be front-page news the 10th time that happens
due to server outages or administrative screwups? I imagine it will be kind
of like using an expired x.509 cert today. People on hackernews might
comment if a top website did it, but not an emergency board meeting type of
situation for that company.

With CT for x.509 certs the assumption is that smaller number of logs are
run which are very important and any screwup is a BFD. I don't know if that
assumption scales to thousands of DNSSEC-CT logs.

> Remember, com. and . cannot merely MITM  com. would have
> to MITM as well.  And . would have to MITM com. too.  These
> would be noticeable.

What about a compelled creation attack (or undetected key compromise) where
malicious entries are signed by the genuine key? For example, say gives me and I care that they only
sign my records for this domain so that nobody can MITM my site. But they
secretly agree to give the government of Elbonia a signed record for my
domain and then fail to log them properly. They can do this without any
compromise or intervention of com, right?