CVE-2026-110863
Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers
CVSS Score
8.1
EPSS Score
0.0%
EPSS Percentile
0th
Better Auth @better-auth/sso from 1.7.0-rc.2 before 1.7.3 contains an authentication bypass vulnerability that allows authenticated users to sign in as other users by registering a personal SSO provider. Attackers can copy a legitimate provider's OIDC issuer or SAML entity ID and assert a victim's subject or NameID, because account lookup ignores providerId, creating sessions for victim accounts.
| CWE | CWE-287 |
| Vendor | better-auth |
| Product | sso |
| Published | Oct 14, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
better-auth / sso
1.7.0-rc.2 < 1.7.3
References
Credits
🔍 manus-use