CVE-2026-110864

Better Auth from 1.5.0-beta.12 before 1.7.7 contains an authentication bypass vulnerability in the OAuth Proxy plugin that allows unauthenticated attackers to sign in as other users by forging encrypted profiles. When the proxy shares the global secret and cookie-stored state is used, attackers can obtain encrypted state for a fake profile with a victim's verified email to take over the account via implicit linking.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/better-auth/better-auth/security/advisories/GHSA-r4xp-prcw-77qf
https://www.vulncheck.com/advisories/better-auth-1.5.0-beta.12-before-1.7.7-authentication-bypass-via-oauth-proxy

Configurations

No configuration.

History

14 Oct 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 23:17

Updated : 2026-10-16 18:25

NVD link : CVE-2026-110864

Mitre link : CVE-2026-110864

CVE.ORG link : CVE-2026-110864

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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