[OAUTH-WG] Re: [agent2agent] Review of draft-rosenberg-oauth-aauth-00

[Patrick White <[e-mail]>]

Scope descriptions allows the model to make a decision about request a
particular scope AND provides a standardized mechanism to present scopes to
users out of band. Maybe there's a thinking that the authorization server
is always so tightly coupled to the application that it should have the
natural language descriptions of scopes available directly in it?

On Thu, Jul 24, 2025 at 10:05 AM Nick Watson <[e-mail]> wrote:

> RFC 9728 already provides a lot of natural language descriptions of
> resource APIs - what would scope descriptions add over that?
>
> I agree with Jeff that CIBA + RFC 9728 seems like it would address this,
> and we should avoid agents' passing PII around as an authn mechanism.
>
> On Tue, Jul 22, 2025 at 7:52 PM Lombardo, Jeff <jeffsec=
> [e-mail]> wrote:
>
>> The scopes to be defined that still can be an AI agent role based on the
>> task at stake. There is no issue with that cause the scopes have to be
>> provided on the Authorization request to the AS.
>>
>> My problem is the authentication flow going through the Agent and being
>> based on PII. I would prefer an Out-of-Band Authentication if possible, and
>> if not at least a dynamic authentication.
>>
>> In this case, event a battlecard authentication would be better than a
>> PII “authentication”, like the AS asking through the Agent give A-9, D-16,
>> and E-4 for the user to retrieve the corresponding answer from its secret
>> sheet.
>>
>>
>>
>> The flow for OOB [which is exactly CIBA] would like in a picture:
>>
>>
>>
>>
>>
>> Here is a Mermaid link to the live Editor:
>> https://mermaid.live/edit#pako:eNqlVu9v2jAQ_VdO_rJOY1XapYVEVaeO7kO_TAj2Q5qQKpMcwapjZ45Txqr-7zs7YYUQYNP6qYnv3r17fnfkiSU6RRazEn9UqBK8FTwzPJ8qoL8RN1YkouDKwo0UCe55_aqEm8ouUNFrboVWcIuPneGTqii0obQ7uMkovo6Y6Z8eQBvxq86foHlEU5-2MYZSUCaMMROlNXX8R5UWWqzxdkhuYR-O_awfsB1DT7utjLHUlUlwi6uX4-rq7dvr64PKxHUkiBKM7wMNpkDHFAupD4G5Nv6RF4VssusibRHreodkievEFuWGZ6c4cTvYUS2MtphYYjpbHbiwTxQF2uW0mcY7bxxswgs-k5Qyhw0Vidqb3fyr0efJJ1BVPkMjVHZ9vKJInfpzQYe5yBYWZk5hIx6pjbnROeRoecotr5-c4gmXsgdSPCCsdOUfKao-501xuIMHpZfdN-K4-yZi-IYy0ZRsNZCcdMVSKFdBEcCCP_oKZoPk-6MS3AHPN8fxUPEFt02tVHtDuX6sTvnqb-osnc-JuEGFS8hXZAAsEyMKf-V0XUKVFfVz_BJuveBQJrrAshbSuI1T2uO5Q4OcTjmMRbJo2W68CdIpxB53N6Dbxw0lWAq7gMTP071Ie0BgSBNFhqkbIG_oTKj7BUHBiZfwdSNnZ7lufW8SZyCJaYa5m4QTTsn3xIFqNnBS6wK-kDMk8E6mbnq0Kikd05d91iXE9l6LYaTJ1NsvvUHmUi8JMy8kvmwcXC_A_f0dWXcTggClncebEy9ySrMnZAknXtjei-ivN-y5D3XD6COJvMTNMGz5-9g63sgk2d3Ir_6NQmPF9X3QcnKj4_vywv5p7d-IDWs4h-XW0HqC9gAe5LlnFL5yKdLdYTg6Wv_lqO247gEZo62MakIneIBK67eKuKCh0rQmR3cwdLp5t203-AG5oYXj4VmP5WhyLlL6FnpyhaaMZMxxymL6N8U5r6Sdsql6plCaRT1ZqYTF1lTYY0ZX2YLFcy5LeqoKp2bzIfXnLX0zfNc6X6dkxpVq0mk20Ax1pSyLw7NB4KNZ_MR-svjsXXgaBYP-xXkYnoXB5flFj61YPIhOg4soiPrnURC8i4LL5x775fGD00E_jKKoH52F4eDysh8-_wa4dWW_
>>
>>
>>
>> Here is the Mermaid for those who could not see the picture nor use the
>> link:
>>
>> sequenceDiagram
>>
>>     Participant Alice
>>
>>     Participant Alice's Authentication Device
>>
>>     Participant Support AI Agent
>>
>>     box Authorization Server
>>
>>         Participant Client Registration Endpoint
>>
>>         Participant Authorization Endpoint
>>
>>         Participant Token Endpoint
>>
>>     End
>>
>>     Participant Resource Server
>>
>>     Alice<<-->>Alice's Authentication Device: Alice is registered on the
>> device for the application
>>
>>     Support AI Agent<<-->>Client Registration Endpoint:
>>
>>     Resource Server<<-->>Authorization Endpoint: Resource Server is
>> protected by Authorization Server
>>
>>     Note over Support AI Agent: Support AI Agent is capable of
>>
>>     Alice->>+Support AI Agent: <PTSN numbering>
>>
>>     Note over Support AI Agent: identifier might be derived from metadata
>> from the call, like you call me from a number I know
>>
>>     Support AI Agent->>+Alice: Welcome to our online can I have your
>> identifier?
>>
>>     Alice->>+Support AI Agent: I am Alice
>>
>>     Support AI Agent->>+Alice: What can I do for you today?
>>
>>     Alice->>+Support AI Agent: I want to renew my prescription of insulin
>>
>>     Note over Support AI Agent: Derive scopes from request
>>
>>     Note over Support AI Agent: Create a Rich Authorization Request
>>
>>     Support AI Agent->>+Authorization Endpoint: Create Authorization
>> request with client_id, generated scopes, login_hint *(*Alice*)*
>>
>>     Authorization Endpoint->>+Support AI Agent: Acknowledgement *(*
>> auth_req_id*)*
>>
>>     loop Until authorization request is consented
>>
>>         Support AI Agent->>+Token Endpoint: Poll Token Endpoint for flow
>> completion
>>
>>     end
>>
>>     Authorization Endpoint->>+Alice's Authentication Device: Send
>> notification with details *(*scope*,* client_id*)*
>>
>>     Alice's Authentication Device->>+Alice: Please Authenticate
>>
>>     Alice->>+Alice's Authentication Device: Authenticate locally
>>
>>     Alice's Authentication Device->>+Alice: Request consenting to scope
>> for client_id
>>
>>     Alice->>+Alice's Authentication Device: Consent to all scopes for
>> client_id
>>
>>     Alice's Authentication Device->>+Authorization Endpoint: Validate
>> Authorization Request
>>
>>     Support AI Agent->>+Token Endpoint: Poll Token Endpoint for flow
>> completion
>>
>>     Token Endpoint->>+Support AI Agent: Return Token Set
>>
>>     Support AI Agent->>+Resource Server: Perform API Call with
>> Authorization Bearer Token
>>
>>
>>
>>
>>
>> *Jean-François “Jeff” Lombardo* | Amazon Web Services
>>
>>
>>
>> Architecte Principal de Solutions, Spécialiste de Sécurité
>> Principal Solution Architect, Security Specialist
>> Montréal, Canada
>>
>> ( [phone] <(514)%20778-5565>
>>
>> *Commentaires à propos de notre échange? **Exprimez-vous **ici*
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>>
>>
>>
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>>
>>
>>
>> *From:* Patrick White <[e-mail]>
>> *Sent:* July 22, 2025 7:09 PM
>> *To:* Lombardo, Jeff <jeffsec=[e-mail]>
>> *Cc:* [e-mail]; [e-mail]; Lombardo, Jeff <
>> [e-mail]>
>> *Subject:* RE: [EXT] [agent2agent] Review of
>> draft-rosenberg-oauth-aauth-00
>>
>>
>>
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>>
>>
>> Hey Jeff, someone pointed out the OIDC HITL spec here, there's absolutely
>> some overlap, but one of the big things that missing is natural language
>> descriptions of scopes (well, and also that it's not an oauth flow, but I'm
>> not sure how much that matters). At a high level, a really important part
>> of the AAuth stuff I proposed is tooling to allow the LLMs to actually
>> discover what scopes they need. You could do it as part of a dance (I make
>> a request, get the scope demand, then flow that through), but I was trying
>> for a model where the models themselves would craft the scope request based
>> on the well known scope definition document. Maybe I missed something
>> around natural language scope definitions in the OIDC spec, though
>>
>>
>>
>> On Tue, Jul 22, 2025 at 7:01 PM Lombardo, Jeff <jeffsec=
>> [e-mail]> wrote:
>>
>> [+ OAuth WG as this touches their core specs]
>>
>> Thanks Jonathan and Pat for putting that forward.
>>
>>
>>
>> Here are some comments / questions / suggestions:
>>
>>
>>
>>    - The use cases are very clear and are very good thought experiments
>>    to rubberstamp / challenge the models of delegated authorization we have
>>    build so far
>>
>>
>>
>>    - Unfortunately, the proposition seems to point towards a glorified
>>    Knowledge Based Authentication (KBA) as it will use PII validation to
>>    authenticate  as a form of “password” in a glorified Resource Owner
>>    Password Grant type flow as the request is only dealing with the Token
>>    endpoint… the problems are:
>>
>>
>>    - Knowledge Based Authentication is highly insecure cause anyone that
>>       knowing this static information can impersonate someone else
>>       - It is based on PII which are Identifiers and not Authentication
>>       factors, therefore can only allow to identify someone. On top of that, PII
>>       leak constantly and are no longer considered secure
>>
>>
>>    - Also what would prevent the AI agent to fetch those information
>>          from the internet on behalf od the user as you noted into section *3.1.
>>          <https://datatracker.ietf.org/doc/html/draft-rosenberg-oauth-aauth#section-3.1>Basic
>>          Token Flow
>>          <https://datatracker.ietf.org/doc/html/draft-rosenberg-oauth-aauth#name-basic-token-flow>
>>          *
>>
>>
>>
>> *By altering the required set of PII elements, designers of AI Agents can
>> control the likelihood of hallucination (or malicious prompt injection
>> attacks) resulting in a token issuance for the wrong user. The selection of
>> the information becomes even more important for AI Agents. Usage of PII
>> elements which are known publically becomes a real risk. If these are
>> included in the training data for the LLM, it is indeed possible (and
>> likely) that the LLM would hallucinate it. For example, if the patient in
>> question is a famous actor, and their date of birth is public record in the
>> IMDB, it is likely that the LLM would hallucinate the date of birth.
>> Consequently, the Authorization Servers can be configured to require
>> sufficient number and complexity of PII in order to provide the desired
>> level of security.*
>>
>>
>>
>>    - This hardly advocates for the PII to not flow through the AI cause
>>          thinking the AS will be smarter than the AI* by configured to
>>          require sufficient number and complexity of PII in order to provide the
>>          desired level of security *is a false expectation
>>
>>
>>
>>    - Resource Owner Password Grant flow is obsolete and deprecated see
>>       https://www.rfc-editor.org/rfc/rfc9700.html#name-resource-owner-password-cre
>>
>>
>>
>>    - Without consideration about the above points we are exchanging an
>>    AI Agent risk by a very secure AI Agent that could on very misleading /
>>    spoofable / malicious crafted information. I don’t think this better.
>>
>>
>>
>>    - Have you evaluated Client Initiated Backchannel Authorization grant
>>    type flow [
>>    https://openid.net/specs/openid-client-initiated-backchannel-authentication-core-1_0.html
>>    ] before designing this new specification?
>>
>>
>>    - This would perfectly fit into the following specification statement
>>       in section *3.2.
>>       <https://datatracker.ietf.org/doc/html/draft-rosenberg-oauth-aauth#section-3.2>Human-In-The-Loop
>>       <https://datatracker.ietf.org/doc/html/draft-rosenberg-oauth-aauth#name-human-in-the-loop>
>>       *
>>
>>       *Initiate the consent review flow with the user. This spec does
>>       not specify how this occurs, it could be through an app, a chat client, or
>>       some other mechanism.*
>>
>>
>>
>> My 0.02 Canadian Dollars
>>
>>
>>
>> Jeff
>>
>>
>>
>> *Jean-François “Jeff” Lombardo* | Amazon Web Services
>>
>>
>>
>> Architecte Principal de Solutions, Spécialiste de Sécurité
>> Principal Solution Architect, Security Specialist
>> Montréal, Canada
>>
>> ( [phone]
>>
>> *Commentaires à propos de notre échange? Exprimez-vous **ici*
>> <https://urldefense.com/v3/__https:/feedback.aws.amazon.com/?ea=jeffsec&fn=Jean*20Francois&ln=Lombardo__;JQ!!Pe07N362zA!0k9CkAV8Djpw_8EfIAKrbhP3TQrJr0oMnznlUgBJ3V3NoEk6hihx7dNHnQuejn6SSH2CP8Iow3G-tTzppHeg$>
>> *.*
>>
>>
>>
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>>
>>
>>
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