CVE-2026-53516

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

Published Jul 15, 2026 CVSS 3.1 · 8.3 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-g38m-r43w-p2q7 Better Auth has an account takeover issue via OAuth auto-link to unverified pre-registered email
History
Type Values Removed Values Added
First Time appeared Better-auth
Better-auth better Auth
Vendors & Products Better-auth
Better-auth better Auth
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Better Auth: Account takeover via OAuth auto-link to unverified pre-registered email
Weaknesses CWE-287
CWE-345
References
Metrics cvssV3_1

{'score': 8.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jul 15, 2026, 5:52 PM
Reserved
Jun 9, 2026, 5:30 PM
Status
Analyzed
Published
Jul 15, 2026, 6:16 PM
Modified
Jul 21, 2026, 2:14 PM