Re: [TLS] [pkix] Cert Enumeration and Key Assurance With DNSSEC

Peter Gutmann <> Sun, 03 October 2010 04:13 UTC

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From: Peter Gutmann <>
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Date: Sun, 03 Oct 2010 17:14:06 +1300
Subject: Re: [TLS] [pkix] Cert Enumeration and Key Assurance With DNSSEC
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Phillip Hallam-Baker <> writes:

>The attack surface is the number of paths that are open to an attacker.
>In the current model there is only one trust path, the PKIX path.

Which isn't so much a path as a twelve-lane motorway with elevated cloverleaf
interchanges, twenty-four-hour drive-through catering stops, and large neon
signs every few km inviting every attacker to join in.

>In the new model, the attacker has a choice of trust paths, the PKIX path and
>the DNSSEC path and they can attack either of them.

Or you can block off the PKIX motorway and leave only the (possibly) smaller
DNSSEC two-lane road.

(I'm not sure whether DNSSEC has a smaller overall attack surface than PKIX,
but chances are it does because the only security protocol with an even larger
attack surface than PKIX is XMLsec, whose attack surface is so huge that it
won't fit on the planets surface but actually extends several km out into