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Re: IETF mail server and SSLv3

Viktor Dukhovni <ietf-dane@dukhovni.org> Fri, 26 February 2016 23:47 UTC

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Subject: Re: IETF mail server and SSLv3
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Date: Fri, 26 Feb 2016 18:46:46 -0500
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> On Feb 26, 2016, at 6:02 PM, Solarus <solarus@ultrawaves.fr> wrote:
> 
>>> Disabling SSLv3 can not possibly provide any security benefit here,
>>> but may cause interop problems and less security for a few old peers.
>> 
>> Would you then go further and say that SMTP servers should leave SSLv2
>> and/or EXPORT ciphers or single-DES enabled?  If not, why not?
> 
> No.

"No" as in they should not leave SSLv2/EXPORT/1DES enabled?

> But with SMTP, STARTTLS is an opportunistic encryption, if you don't
> support the maximum of ciphers, the other server will send you mails in
> cleartext.
> And it's worse to receive and send mail in cleartext than with a weak
> encryption.

Your rationale seems to contradict the "No" response.

-- 
	Viktor.

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