Intel

AIKIDO-2026-11111

@better-auth/oauth-provider is vulnerable to Incorrect Authorization

Incorrect Authorization Pre-CVE
Found by Aikido Intel before public disclosure or CVE publication.
Published 3 days ago

71

High Risk

This Affects:

JS@better-auth/oauth-provider
1.4.8 - 1.6.12
Fixed in 1.6.13
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TL;DR

Dynamic client registration at POST /oauth2/register reached OAuth client persistence without running the configured clientPrivileges create gate, while the other client-creation routes enforced it. Deployments that relied on clientPrivileges to restrict who can register clients could still let authenticated users register confidential clients with attacker-chosen redirect URIs and metadata. The fix enforces the create check in the shared createOAuthClientEndpoint chokepoint for every registration path when a session is present.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range.

Background info

@better-auth/oauth-provider is vulnerable to Incorrect Authorization in versions 1.4.8 - 1.6.12.

How to fix this

Upgrade the @better-auth/oauth-provider library to the patch version.