CVE-2026-41427

MEDIUM

Better Auth OAuth 2.1 Provider: Unprivileged users can register OAuth clients

Title source: cna
STIX 2.1

Description

Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.5, the clientPrivileges option documents a create action, but the OAuth client creation endpoints did not invoke the hook before persisting new clients. Deployments that configured clientPrivileges to restrict client registration were not actually restricted — any authenticated user could reach the create endpoints and register an OAuth client with attacker-chosen redirect URIs and metadata. This vulnerability is fixed in 1.6.5.

References (1)

Core 1
Core References

Scores

CVSS v3 6.5
EPSS 0.0021
EPSS Percentile 11.4%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-863
Status published
Products (8)
better-auth/better-auth >= 1.4.8-beta.7, < 1.6.5
better-auth/better-auth >= 1.7.0-beta.0, <= 1.7.0-beta.1
better-auth/better-auth\/oauth-provider 1.4.8 (2 CPE variants)
better-auth/better-auth\/oauth-provider 1.7.0 beta0
better-auth/better-auth\/oauth-provider 1.4.9 - 1.6.5
better-auth/oauth-provider 1.4.8-beta.7 - 1.6.5npm
better-auth/oauth-provider >= 1.4.8-beta.7, < 1.6.5
better-auth/oauth-provider >= 1.7.0-beta.0, <= 1.7.0-beta.1
Published Apr 24, 2026
Tracked Since Apr 24, 2026