Why I can no longer support OAuth2 (was: Re: Why can't I pay using a Verifiable Credential?)

On Wed, Aug 13, 2025 at 5:18 PM Tim Bouma <trbouma@gmail.com> wrote:
> Several months back I took a hard look at OAuth and what I learned from my implementation endeavour, I wrote this.
>
> https://open.substack.com/pub/trbouma/p/why-i-can-no-longer-support-oauth

This is an excellent article, Tim. It matches our experience at
Digital Bazaar implementing both OAuth2 and the OID4VCI/OID4VP
protocols. We have repeatedly experienced developers in the ecosystem
accidentally leak their credentials via OAuth2 because of a lack of
understanding in how it works, or the pitfalls with "framework-based
standards".

OAuth2 was what drove us to incubate and standardize HTTP Signatures,
which does at least depend on cryptography to prove authorization.

Dick Hardt has recently written a related post on how OAuth2 is not a
good fit for things like MCP (and how HTTP Message Signatures are
better):

https://www.linkedin.com/posts/dickhardt_mcp-oauth-ai-activity-7358178115673616384-RKzc/

... granted, he still tries to loop OAuth2 back into the mix (a
mistake, IMHO -- we should just leave OAuth2 behind and move on to
stuff like Authorization Capabilities), but dropping the complicated
OAuth2 dances for clients is certainly an improvement.

In any case, just wanted to echo what you wrote Tim -- OAuth2 was
better than sharing passwords a decade or more ago, but we need to
move on to real cryptographic authentication, authorization, and
delegation.

-- manu

-- 
Manu Sporny - https://www.linkedin.com/in/manusporny/
Founder/CEO - Digital Bazaar, Inc.
https://www.digitalbazaar.com/

Received on Sunday, 17 August 2025 16:51:34 UTC