Re: [OAUTH-WG] WGLC for "OAuth 2.0 Security Best Current Practice"

Torsten Lodderstedt <torsten@lodderstedt.net> Tue, 19 November 2019 06:17 UTC

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From: Torsten Lodderstedt <torsten@lodderstedt.net>
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Date: Tue, 19 Nov 2019 14:17:02 +0800
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Cc: Hannes Tschofenig <Hannes.Tschofenig@arm.com>, "oauth@ietf.org" <oauth@ietf.org>
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To: Vineet Banga <vineetbanga@google.com>
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Subject: Re: [OAUTH-WG] WGLC for "OAuth 2.0 Security Best Current Practice"
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> Am 19.11.2019 um 13:39 schrieb Vineet Banga <vineetbanga@google.com>om>:
> 
> Let me restate my original question. I agree with the usage of state for CSRF protection, but it can also be used to capture the application state (as specified in: [I-D.bradley-oauth-jwt-encoded-state]). I am asking if there is any recommendation between using state for both csrf and application state Vs. relying completely on redirect URIs to maintain application state.
> 
> As an OAuth provider, I lean towards avoiding long and dynamic list of redirect URIs. But I do understand that using state for both CSRF protection and application state adds burden on clients/app developers. 

got you, thanks for the clarification.

I would recommend to use PKCE for CSRF prevention and state for representing the application state.

best regards,
Torsten.