CVE-2026-110862

Better Auth from 1.4.0-beta.18 before 1.7.7 contains an authentication bypass vulnerability that allows unauthenticated attackers to sign in as other users by reusing OAuth state values as Magic Link tokens. Attackers can start an OAuth sign-in with a victim's email and submit the returned state to Magic Link verification, gaining sessions or creating falsely email-verified accounts.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

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-965c-763c-88jm
https://www.vulncheck.com/advisories/better-auth-1.4.0-beta.18-before-1.7.7-authentication-bypass-via-magic-link

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-2026-110862

Mitre link : CVE-2026-110862

CVE.ORG link : CVE-2026-110862

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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