Re: [websec] Question regarding RFC 6797

Anne van Kesteren <annevk@annevk.nl> Mon, 28 May 2018 11:21 UTC

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From: Anne van Kesteren <annevk@annevk.nl>
Date: Mon, 28 May 2018 13:21:02 +0200
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To: Claudio Saavedra <csaavedra@igalia.com>
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Subject: Re: [websec] Question regarding RFC 6797
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On Mon, May 28, 2018 at 10:20 AM, Claudio Saavedra <csaavedra@igalia.com> wrote:
> Section 8.1 states:
>
>    Update the UA's cached information for the Known HSTS Host if either
>    or both of the max-age and includeSubDomains header field value
>    tokens are conveying information different than that already
>    maintained by the UA.
>
> The way I understand this is that if a HSTS host keeps sending the same
> values to a conforming client, this should not update the information
> cached and hence the cached information will expire after max-age
> seconds have passed since the _first_reception_ of this header.

I have a hard time reading it another way as well; if true, this would
be a security bug.


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