[OAUTH-WG] Open redirector feedback (Yaron Goland)

Eran Hammer-Lahav <eran@hueniverse.com> Tue, 16 August 2011 21:45 UTC

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From: Eran Hammer-Lahav <eran@hueniverse.com>
To: OAuth WG <oauth@ietf.org>
Date: Tue, 16 Aug 2011 14:44:47 -0700
Thread-Topic: Open redirector feedback (Yaron Goland)
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Subject: [OAUTH-WG] Open redirector feedback (Yaron Goland)
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Moved here to help discuss.


> 3.1.2.4.  Invalid Endpoint: Comment on "open redirector": "How many people

> even know what the heck an open redirector is? I think we need a section in

> the security considerations section that defines what an open redirector is

> and why it's bad. Alternatively a normative reference to a complete

> definition somewhere else is also fine."

Added new section and reference to it:

10.15.  Open Redirectors

   The authorization server authorization endpoint and the client
   redirection endpoint can be improperly configured and operate as open
   redirectors.  An open redirector is an endpoint using a parameter to
   automatically redirect a user-agent to the location specified by the
   parameter value without any validation.

   Open redirectors can be used in phishing attacks to get end-users to
   visit malicious sites by making the URI's authority look like a
  familiar and trusted destination.  In addition, if the authorization
   server allows the client to register only part of the redirection
   URI, an attacker can use an open redirector operated by the client to
   construct a redirection URI that will pass the authorization server
   validation but will send the authorization code or access token to an
   endpoint under the control of the attacker.