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Re: [TLS] An SCSV to stop TLS fallback.

"Yngve N. Pettersen" <yngve@spec-work.net> Thu, 05 December 2013 02:15 UTC

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Date: Thu, 05 Dec 2013 03:15:45 +0100
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From: "Yngve N. Pettersen" <yngve@spec-work.net>
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Subject: Re: [TLS] An SCSV to stop TLS fallback.
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On Thu, 05 Dec 2013 01:52:34 +0100, James Cloos <cloos@jhcloos.com> wrote:

>>>>>> "DS" == Douglas Stebila <stebila@qut.edu.au> writes:
>
> DS> Does anyone on the list know of an example website where one can
> DS> observe a potentially attackable TLS fallback?
>
> I do not know the extent to which it is attackable, but  
> https://archive.org
> (aka www.archive.org) only works with ssl/3.0.  TLS-only clients cannot
> connect thereto.

This site may be SSL v3.0-only, but it is version and extension tolerant  
up to at least version bytes 3.4, as well as for 4.1. It is also Renego  
patched, and AFAICT support SNI and ECDHE_RSA. Given the latter two, I  
wonder if the server is actually able to support at least TLS 1.0, but  
that it have been disabled somehow, perhaps due to an old configuration  
setting that only specifies SSL v3 as enabled (perhaps in order to disable  
SSL v2).

-- 
Sincerely,
Yngve N. Pettersen

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