CVE-2026-67328

@better-auth/sso versions before 1.6.21 contain multiple authentication bypass vulnerabilities in SSO provider handling that allow attackers to sign in as arbitrary users. Attackers can exploit domain verification parsing mismatches, orphaned provider accounts, unbound SAML assertions, or reflected XSS on logout endpoints to gain unauthorized session access and account takeover.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

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-prpr-5gj3-qqhg
https://www.vulncheck.com/advisories/better-auth-sso-before-account-takeover-via-sso

Configurations

No configuration.

History

01 Aug 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-08-01 13:17

Updated : 2026-08-01 13:17

NVD link : CVE-2026-67328

Mitre link : CVE-2026-67328

CVE.ORG link : CVE-2026-67328

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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