Re: [websec] Issue 55 - Key pinning should clarify that the newest pinning information takes precedence

Tom Ritter <> Wed, 06 March 2013 02:56 UTC

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From: Tom Ritter <>
Date: Tue, 5 Mar 2013 21:55:42 -0500
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Subject: Re: [websec] Issue 55 - Key pinning should clarify that the newest pinning information takes precedence
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On 4 March 2013 19:57, Ryan Sleevi <> wrote:
> The authors belief is that the issues that arise from either
> implementations are artifacts of the implementation and distribution of
> preloaded pins, rather than an issue intrinsic to this specification. That
> is, the "correct" answer is that the preloaded pin list should be updated
> for Site 1 - however that information is distributed between the site
> operator and the creator of the preloaded pin list.
> Are there concerns with this interpretation, or can we close out Issue 55?

I guess I'm just confused.  I agree it's rife for implementation
differences, but I either
A) Incorrectly parse this as punting on guidance that would (try to)
achieve parity across implementations and prevent yet another thing
that webmasters need to understand when requesting preloading in
multiple browsers
b) Correctly parse it as such, but don't understand why you would punt
on expressing a standard behavior instead.