Re: [OAUTH-WG] security considerations for draft-ietf-oauth-mtls-12

Brian Campbell <bcampbell@pingidentity.com> Thu, 01 November 2018 14:37 UTC

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From: Brian Campbell <bcampbell@pingidentity.com>
Date: Thu, 01 Nov 2018 08:37:11 -0600
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Subject: Re: [OAUTH-WG] security considerations for draft-ietf-oauth-mtls-12
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To be honest, I thought that was a relatively well known aspect of TLS 1.2
(and prior) and a noted difference of the new features in TLS 1.3. Also,
I'd note that we're well past WGCL for this document. But, with that said,
I suppose adding some privacy considerations text on the subject is
worthwhile. Would you propose some text for the WG to consider, John-Mark?
Bearing in mind that the implications of a certificate presented by, and
representing, an OAuth client are somewhat different than for an end-user
doing client cert authentication.




On Wed, Oct 31, 2018 at 4:12 PM John-Mark Gurney <jmg+oauth@newcontext.com>
wrote:

> I would suggest that the security considerations section of
> draft-ietf-oauth-mtls-12 be expanded to include the privacy
> implications of using this on versions of TLS before 1.3.  On all
> versions of TLS before 1.3, the client cert is not encrypted and can
> be used by third parties to monitor and track users.  I recently
> posted a blog entry about this:
> https://blog.funkthat.com/2018/10/tls-client-authentication-leaks-user.html
>
> Thanks.
>
> John-Mark Gurney
>
> _______________________________________________
> OAuth mailing list
> OAuth@ietf.org
> https://www.ietf.org/mailman/listinfo/oauth
>

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