CVE-2026-110863EPSS p17.8%
CVE-2026-110863CVE-2026-110863
Description
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.
Scoring
| CVSS | 8.1 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
| EPSS | 0.27% probability of exploitation · percentile 17.8% · 2026-10-17T12:00:28Z |
| Last modified | 2026-10-16 |