Authentication Bypass Using an Alternate Path or Channel Affecting @better-auth/core package, versions <1.6.11
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published8 Jul 2026
- disclosed7 Jul 2026
- creditavrm
Introduced: 7 Jul 2026
NewCVE-2026-53516 (opens in a new tab)How to fix?
Upgrade @better-auth/core to version 1.6.11 or higher.
Overview
@better-auth/core is a The most comprehensive authentication framework for TypeScript.
Affected versions of this package are vulnerable to Authentication Bypass Using an Alternate Path or Channel in the handleOAuthUserInfo. An attacker can gain unauthorized access to user accounts by pre-registering a victim's email address and leveraging OAuth or SSO providers that assert email_verified: true, which allows the attacker's account to be implicitly linked to the victim's OAuth identity. This results in the attacker obtaining both password and OAuth login access to the same account.
Note: This is only exploitable if the application has emailAndPassword.enabled: true, at least one OAuth or SSO provider configured, account.accountLinking.disableImplicitLinking is not set to true, and account.accountLinking.enabled is not set to false.
Workaround
This vulnerability can be mitigated by setting account.accountLinking.disableImplicitLinking: true to force all linking through authenticated endpoints, or by setting account.accountLinking.enabled: false to disable linking entirely.