CVE-2026-109082

EUVD-2026-97260
A flaw was found in the Client-Initiated Backchannel Authentication CIBA implementation within the keycloak-services component of Keycloak. This component handles advanced authentication flows where a client initiates a login on behalf of a user. The issue occurs because Keycloak fails to verify that a client is authorized to use the CIBA flow, allowing public clients to bypass security requirements. An attacker could use this flaw to trick a user into approving a login request, eventually gaining full access to the users account without needing a client secret.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.8 MEDIUM
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N