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Re: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)

Martin Thomson <martin.thomson@gmail.com> Sat, 18 October 2014 00:16 UTC

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Date: Fri, 17 Oct 2014 17:16:25 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Andrei Popov <Andrei.Popov@microsoft.com>
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Subject: Re: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)
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On 17 October 2014 16:54, Andrei Popov <Andrei.Popov@microsoft.com> wrote:
> Correct; however thanks to POODLE, these auto-downgrading client applications are rapidly removing SSL3 from the fallback sequence. So the reason for having SCSV (instead of a proper TLS extension) is disappearing.

I think on balance it's worth leaving this.  I expect NSS will
maintain SSLv3 for some time to come for various reasons that I don't
like, but am willing to tolerate.  The SCSV is going to provide a
measure of protection to those people who are forced to allow it to
live.

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