[Openid-specs-fapi] [Openid-specs-mobile-profile] Source authentication on client notification endpoint

Dave Tonge dave.tonge at momentumft.co.uk
Mon Nov 13 09:29:50 UTC 2017


Hi Torsten

Good question. So the general principle was not relying purely on a bearer
token from the OP to the Client.
>From my perspective the threat model is something like this:
 - The client_notification_endpoint is only protected by a bearer token
 - This bearer token could leak which could allow a malicious actor to
deliver the wrong access token to the client
 - For example, a MITM between the OP and the Client could intercept two
CIBA notification callbacks and swap the access tokens. The proposal would
at least bind the access token to the id token.

To fully prevent the above attack the auth_req_id (or a hash of it should
probably also be included in the id_token).

John or Nat may have a view on this as well?

Dave

On 12 November 2017 at 04:01, Torsten Lodderstedt <torsten at lodderstedt.net>
wrote:

> Hi Dave,
>
> Am 07.11.2017 um 00:35 schrieb Dave Tonge <dave.tonge at momentumft.co.uk>:
>
> he token response sent to this endpoint has an id_token. We suggested that
> this id_token should include an `at_hash`. This will give the client
> greater assurance that the token response is from the OpenID Provider and
> of the integrity of the payload.
>
>
> can you elaborate on the threat model underpinning this decision?
>
> best regards,
> Torsten.
>
>


-- 
Dave Tonge
CTO
[image: Moneyhub Enterprise]
<http://www.google.com/url?q=http%3A%2F%2Fmoneyhubenterprise.com%2F&sa=D&sntz=1&usg=AFQjCNGUnR5opJv5S1uZOVg8aISwPKAv3A>
10 Temple Back, Bristol, BS1 6FL
t: +44 (0)117 280 5120

Moneyhub Enterprise is a trading style of Momentum Financial Technology
Limited which is authorised and regulated by the Financial Conduct
Authority ("FCA"). Momentum Financial Technology is entered on the
Financial Services Register (FRN 561538) at fca.org.uk/register. Momentum
Financial Technology is registered in England & Wales, company registration
number 06909772 © . Momentum Financial Technology Limited 2016. DISCLAIMER:
This email (including any attachments) is subject to copyright, and the
information in it is confidential. Use of this email or of any information
in it other than by the addressee is unauthorised and unlawful. Whilst
reasonable efforts are made to ensure that any attachments are virus-free,
it is the recipient's sole responsibility to scan all attachments for
viruses. All calls and emails to and from this company may be monitored and
recorded for legitimate purposes relating to this company's business. Any
opinions expressed in this email (or in any attachments) are those of the
author and do not necessarily represent the opinions of Momentum Financial
Technology Limited or of any other group company.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openid.net/pipermail/openid-specs-fapi/attachments/20171113/9d115191/attachment.html>


More information about the Openid-specs-fapi mailing list