CVE-2026-4634: fallo de gravedad alta en Red Hat build of Keycloak 26.2
Keycloak: keycloak: denial of service via excessive processing of openid connect scope parameters
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 7.5epss 0.6%
A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an excessively long scope parameter to the OpenID Connect (OIDC) token endpoint. This leads to high resource consumption and prolonged processing times, ultimately resulting in a Denial of Service (DoS) for the Keycloak server.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Productos afectados
Red Hat · Red Hat build of Keycloak 26.2Red Hat · Red Hat build of Keycloak 26.2.15Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.11Red Hat · Red Hat Single Sign-On 7.6.13Red Hat · Red Hat Single Sign-On 7.6 for RHEL 7Red Hat · Red Hat Single Sign-On 7.6 for RHEL 8Red Hat · Red Hat Single Sign-On 7.6 for RHEL 9Red Hat · RHEL-8 based Middleware ContainersCVEs relacionadas — Red Hat build of Keycloak 26.2
En el mismo producto, de las más peligrosas a las menos.
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Referencias
https://access.redhat.com/errata/RHSA-2026:6475https://access.redhat.com/errata/RHSA-2026:6476https://access.redhat.com/errata/RHSA-2026:6477https://access.redhat.com/errata/RHSA-2026:6478https://access.redhat.com/errata/RHSA-2026:76128https://access.redhat.com/errata/RHSA-2026:76129https://access.redhat.com/errata/RHSA-2026:76130https://access.redhat.com/errata/RHSA-2026:76132https://access.redhat.com/errata/RHSA-2026:76134https://access.redhat.com/security/cve/CVE-2026-4634https://bugzilla.redhat.com/show_bug.cgi?id=2450250https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4634.json