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Re: [dane] Improving DANE S/MIME Privacy

Paul Wouters <paul@nohats.ca> Tue, 11 April 2017 19:15 UTC

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Date: Tue, 11 Apr 2017 15:15:00 -0400
From: Paul Wouters <paul@nohats.ca>
To: Alice Wonder <alice@domblogger.net>
cc: dane@ietf.org
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Subject: Re: [dane] Improving DANE S/MIME Privacy
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On Tue, 11 Apr 2017, Alice Wonder wrote:

> If the serial number for the x.509 certificate is a salt for the hash, then 
> spammers can not determine the validity of an e-mail address from DNS but 
> those who already have the certificate can use DNS to DANE validate the 
> certificate.

Except the whole point of this record is to publish that certificate, so
clearly the spammers have a copy of the serial number too :)

Paul

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