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Re: [TLS] MITM Attacks on Client Authentication after Resumption

Adam Langley <agl@google.com> Wed, 05 March 2014 13:07 UTC

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From: Adam Langley <agl@google.com>
Date: Wed, 05 Mar 2014 08:07:22 -0500
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To: "mrex@sap.com" <mrex@sap.com>
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Subject: Re: [TLS] MITM Attacks on Client Authentication after Resumption
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On Tue, Mar 4, 2014 at 2:56 PM, Martin Rex <mrex@sap.com> wrote:
> A while ago I noticed that it was possible to resume a TLS session
> originally established with https://www.google.com/ when proposing
> that session for resumption to https://docs.google.com/ (not using
> any TLS extension here, neither SNI or TLS session tickets).

Yes, both of these services are terminated by the same frontend
machines and they shared a session cache.

Completely unrelated to this matter, you should find that's no longer
the case. Sessions for www.google.com should no longer be resumable
for docs.google.com.


Cheers

AGL

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