CVE-2026-110863 — Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers
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 registerin…
Published: 2026-10-14 · CVSS: 8.6 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7