CVE-2026-9798

A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:50846
https://access.redhat.com/errata/RHSA-2026:50847
https://access.redhat.com/errata/RHSA-2026:50848
https://access.redhat.com/errata/RHSA-2026:50849
https://access.redhat.com/security/cve/CVE-2026-9798	Mitigation Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2482470	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*

History

26 Oct 2026, 12:10

Type	Values Removed	Values Added
Summary		(es) Se encontró una falla en Keycloak, una solución de gestión de identidad y acceso de código abierto. Cuando una cuenta de usuario se bloquea temporalmente debido a repetidos intentos fallidos de inicio de sesión, un atacante con credenciales de cliente válidas puede explotar el flujo de autenticación de canal de retorno iniciado por el cliente (CIBA) para eludir esta protección contra fuerza bruta. Esto permite intentos de autenticación continuos y emisión de tokens incluso cuando la cuenta debería estar bloqueada, lo que podría permitir intentos adicionales de acceso no autorizado.

Information

Published : 2026-05-28 06:16

Updated : 2026-10-26 12:10

NVD link : CVE-2026-9798

Mitre link : CVE-2026-9798

CVE.ORG link : CVE-2026-9798

JSON object : View

Products Affected

redhat

build_of_keycloak

CWE

CWE-305

Authentication Bypass by Primary Weakness

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