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Re: [Uta] MTA-STS-03 review

ned+uta@mrochek.com Tue, 04 April 2017 19:38 UTC

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Date: Tue, 04 Apr 2017 12:32:58 -0700
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To: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [Uta] MTA-STS-03 review
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> On Tue, Apr 04, 2017 at 04:20:59PM +0200, Daniel Margolis wrote:

> > Can you explain a little more what you mean? The mitigation is to publish a
> > new policy with the correct values, so certainly anyone who does so
> > pre-emptively is not likely to fall victim to a DoS attack.  More
> > specifically, anyone who is _aware_ of this risk should simply ensure
> > untrusted individuals cannot publish content with a certificate for *.
> > example.com on "mta-sts.example.com"; the risk is for domains like (say)
> > tumblr.com who may inadvertently allow that.

> I too found the text in question confusing.  It makes no mention
> the attacker is presumed able to obtain certificates for
> "mta-sts.example.com", but otherwise the description does not make
> much sense.  The DNS TXT record does indeed facilitate recovery
> after the fact by signalling the availability of an updated policy.

> I would also like to encourage the authors to post revised drafts
> more frequently.  Please see:

>     https://www.ietf.org/mail-archive/web/ietf/current/threads.html#101804

+1000.

				Ned

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