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Re: [TLS] Working Group Last Call for draft-ietf-tls-downgrade-scsv-00

Bodo Moeller <bmoeller@acm.org> Wed, 15 October 2014 18:09 UTC

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Date: Wed, 15 Oct 2014 20:09:42 +0200
Message-ID: <CADMpkcLnOh3HGD+urWuo6fPfkX4WfGhwckE0jg5jS2KqD2RuMQ@mail.gmail.com>
From: Bodo Moeller <bmoeller@acm.org>
To: Florian Weimer <fweimer@redhat.com>
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Cc: tls@ietf.org
Subject: Re: [TLS] Working Group Last Call for draft-ietf-tls-downgrade-scsv-00
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"Florian Weimer" <fweimer@redhat.com>:

> *) Deploying an SCSV-enabled browser to users on an intercepting network
will largely knock these users off the net (assuming that SCSV support is
widely deployed in public-facing TLS termination), so such attacks are
hopefully very isolated, or else it's not possible to deploy this feature
in browsers.

Thanks for the value proposition, by the way :-)

Preventing such attacks, of course, is what we consider a feature. Google
servers support the SCSV, and so does the Chrome browser; so we have the
required real-life experience indicating that deploying the SCSV is
practical.

Bodo

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