CVE-2026-53516: Better-Auth Better Auth

High severity, CVSS 8.3. EPSS: 0.3% chance of exploitation in the next 30 days.

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.

Affected products

• Better-Auth Better Auth: before 1.6.11 (fixed in 1.6.11)

Published 2026-07-15. Last modified 2026-07-21.