A AegiFlow
HIGHCVSS 8.1

CVE-2026-53517

CVE-2026-53517 updated by NVD

Modified
2026-07-23
Sources
nvd

Summary

Better Auth is an authentication and authorization library for TypeScript. From 1.4.8-beta.7 until 1.6.11, the @better-auth/oauth-provider POST /oauth2/token endpoint on the refresh_token grant performs a non-atomic read, validate, revoke, and mint sequence on the oauthRefreshToken row, allowing concurrent requests with the same parent refresh token to pass the revoked check and create forked refresh-token families; the vulnerable range also includes embedded better-auth plugin versions before 1.6.0. This issue is fixed in version 1.6.11.

References

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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