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Re: [TLS] simplistic renego protection

Michael D'Errico <mike-list@pobox.com> Fri, 20 November 2009 04:23 UTC

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Date: Thu, 19 Nov 2009 20:24:46 -0800
From: Michael D'Errico <mike-list@pobox.com>
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References: <200911182000.nAIK0Qkm013905@fs4113.wdf.sap.corp> <4B04A792.7040607@jacaranda.org> <B197003731D4874CA41DE7B446BBA3E829CD28F1@TK5EX14MBXW653.wingroup.windeploy.ntdev.microsoft.com> <4B059716.6010309@jacaranda.org> <4B059A60.9000003@jacaranda.org> <4B060EE2.7020504@bolyard.me>
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Subject: Re: [TLS] simplistic renego protection
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Nelson B Bolyard wrote:
> 
> ... what is a "lenient server"?
> Is it a vulnerable server?

Yes.

Some servers apparently cannot function without renegotiation.
They will need to continue providing service to unpatched
clients for some amount of time and thus remain vulnerable.

The solution we publish must make it impossible for a lenient-
but-patched client and a lenient-but-patched server to be
successfully attacked by a MitM using the renegotiation bug.

Mike

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