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Re: [TLS] The risk of misconfiguration

Michael D'Errico <mike-list@pobox.com> Mon, 12 May 2014 03:04 UTC

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Date: Sun, 11 May 2014 20:04:03 -0700
From: Michael D'Errico <mike-list@pobox.com>
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To: Bill Frantz <frantz@pwpconsult.com>
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Subject: Re: [TLS] The risk of misconfiguration
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Bill Frantz wrote:
> 
> Now I recognize that there is a significant footgun in having NULL 
> cypher suites in a mix of protocols offered by a client. One way to 
> reduce the risk is to say, "The server MUST reject any connection 
> attempt where the offered cypher suites include both suites providing 
> encryption and those which have NULL encryption.

Why not have the server choose a non-NULL cipher suite if both types
are offered instead of rejecting the connection?

Mike

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