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Re: [TLS] Verify data in the RI extension?

Nikos Mavrogiannopoulos <nmav@gnutls.org> Fri, 27 November 2009 14:30 UTC

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References: <20091125223502.4265B6C3285@kilo.networkresonance.com> <C733FAC4.6B2F%stefan@aaa-sec.com>
Date: Fri, 27 Nov 2009 16:30:39 +0200
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From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
To: Stefan Santesson <stefan@aaa-sec.com>
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Cc: tls@ietf.org
Subject: Re: [TLS] Verify data in the RI extension?
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On Thu, Nov 26, 2009 at 10:28 AM, Stefan Santesson <stefan@aaa-sec.com> wrote:

> On the contrary, I find it to be good security design not to exchange that
> value as it:
>
> 1) Reduce information leakage to an attacker

Hello,
 How would that be? What scenario do you have in mind? This value has
already been exchanged in the initial finished message exchange and
was protected under the same ciphersuite. Why would this exchange be
less secure? If the attacker can decrypt and see this value, then he
can also see the initial finished value. No new information is given
to him.


regards,
Nikos

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