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Re: [TLS] simplistic renego protection

"Yngve Nysaeter Pettersen" <yngve@opera.com> Wed, 25 November 2009 13:46 UTC

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Date: Wed, 25 Nov 2009 14:45:48 +0100
To: Pasi.Eronen@nokia.com, mrex@sap.com
From: Yngve Nysaeter Pettersen <yngve@opera.com>
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Subject: Re: [TLS] simplistic renego protection
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On Wed, 25 Nov 2009 14:01:19 +0100, <Pasi.Eronen@nokia.com> wrote:

> Having TLS endpoints change their certificates during renegotiation is
> highly likely to confuse many applications (and lead to security

Just an observation: A while back I encountered a big Asian bank whose  
loadbalanced servers were using two different Extended Validation  
certificates, and was switching between those certificates every other  
negotiation. The reason I was investigating the site was that the EV  
indication was flip-flopping on this site, which turned out to be because  
one certificate had a 1024 bit key (which qualifies for EV), the other was  
using a 1023 bit key (which does not qualify for EV). For reference,  
session resume did not work in this case.




-- 
Sincerely,
Yngve N. Pettersen
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Senior Developer		     Email: yngve@opera.com
Opera Software ASA                   http://www.opera.com/
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