Re: [TLS] Wrapping up cached info

Stefan Santesson <stefan@aaa-sec.com> Mon, 24 May 2010 05:39 UTC

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Date: Mon, 24 May 2010 07:22:56 +0200
From: Stefan Santesson <stefan@aaa-sec.com>
To: Brian Smith <brian@briansmith.org>, <tls@ietf.org>
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Thread-Topic: [TLS] Wrapping up cached info
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Subject: Re: [TLS] Wrapping up cached info
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Could you explain why?
What is the attack scenario?

/Stefan


On 10-05-23 11:40 PM, "Brian Smith" <brian@briansmith.org> wrote:

> Stefan Santesson wrote:
>> I will, provided that this seems acceptable still in a few days from now,
>> write up a new draft that captures the changes which then hopefully can be
>> ready for a WGLC.
> 
> There's another issue still. If the server sends the client an information
> item X after the change cipher suite message, then the client must not send
> a hash of that information item in its client hello message on another
> connection, until it has verified the identity of the server on that second
> connection. In other words, the client must ensure that it doesn't leak
> information that would otherwise be confidential--including even certificate
> messages and client certificate cipher suite messages that were received
> over an encrypted connection.
> 
> Regards,
> Brian
>