CVE-2026-9087

A flaw was found in Keycloak. The cross-session verification proof is keyed only by local userId, idpAlias and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account...

CVE-2026-9087: Authorization Bypass Through User-Controlled Key

A flaw was found in Keycloak. The cross-session verification proof is keyed only by local userId, idpAlias and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account...