Vulnerability · Published Jul 15, 2026 · Assigned by GitHub_M

CVE-2026-53516Better Auth: Account takeover via OAuth auto-link to unverified pre-registered email

High 8.3

In plain English

A high-severity improper authentication in better-auth from better-auth. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.3High

Exploit odds (30 days)0.3%top 78.4% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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 packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	better-auth	1.6.11	GHSA-g38m-r43w-p2q7

Affected products (as reported)

Vendor	Product	Versions
better-auth	better-auth	< 1.6.11

Weakness: CWE-287, CWE-345 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L

References

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