CVE-2026-67328

@better-auth/sso before 1.6.21 Account Takeover via SSO

Published Aug 1, 2026 CVSS 4.0 · 8.6 High EPSS < 1% KEV · Not listed
Description
@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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Better-auth better-auth\/sso
CPEs cpe:2.3:a:better-auth:better-auth\/sso:*:*:*:*:*:node.js:*:*
Vendors & Products Better-auth better-auth\/sso
Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
First Time appeared Better-auth
Better-auth sso
Vendors & Products Better-auth
Better-auth sso
Type Values Removed Values Added
Description @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.
Title @better-auth/sso before 1.6.21 Account Takeover via SSO
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 8, 2026, 3:24 PM
Reserved
Jul 29, 2026, 1:07 PM
Status
Deferred
Published
Aug 1, 2026, 1:17 PM
Modified
Oct 23, 2026, 11:10 PM