CVE-2026-53516

HIGH 8.3

Better Auth: Account takeover via OAuth auto-link to unverified pre-registered email

CVSS Score

8.3

EPSS Score

0.0%

EPSS Percentile

0th

Better Auth is an authentication and authorization library for TypeScript. Prior to 1.6.11, Better Auth's OAuth callback auto-link gate in handleOAuthUserInfo accepts implicit account linking when the OAuth provider asserts email_verified: true without requiring the local user row's emailVerified field to also be true, allowing an attacker who pre-registers a victim email through /sign-up/email to bind the victim's OAuth identity to the attacker's account. The same primitive affects one-tap, and emailAndPassword.requireEmailVerification: true does not mitigate the link-time verification change. This issue is fixed in version 1.6.11.

CWE	CWE-287 CWE-345
Vendor	better-auth
Product	better-auth
Published	Jul 15, 2026
Last Updated	Jul 15, 2026

Stay Ahead of the Next One

Get instant alerts for better-auth better-auth

Be the first to know when new high vulnerabilities affecting better-auth better-auth are published — delivered to Slack, Telegram or Discord.

Get Free Alerts → Free · No credit card · 60 sec setup

CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

Low

Affected Versions

better-auth / better-auth

< 1.6.11

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/better-auth/better-auth/security/advisories/GHSA-g38m-r43w-p2q7 github.com: https://github.com/better-auth/better-auth/pull/9578 github.com: https://github.com/better-auth/better-auth/commit/da7e50beee849c59a2ed1ec6b3a38cc6ab9fb563 github.com: https://github.com/better-auth/better-auth/releases/tag/v1.6.11