CVE-2026-16442: fallo de gravedad alta en Red Hat build of Keycloak 26.4
Keycloak-services: keycloak-services: saml idp-initiated broker login bypasses link-only restriction
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 7.4epss 0.3%
A flaw was found in the SAML broker component of Keycloak, which is used to manage identity federation and user authentication. The issue occurs because the IdP-initiated Single Sign-On endpoint fails to check if a provider is restricted to account linking only. This allows an attacker with control over a linked upstream identity to bypass login restrictions and gain full access to a local user account.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Productos afectados
Red Hat · Red Hat build of Keycloak 26.4Red Hat · Red Hat build of Keycloak 26.4.14Red Hat · Red Hat build of Keycloak 26.6Red Hat · Red Hat build of Keycloak 26.6.5Red Hat · Red Hat Data Grid 8Red Hat · Red Hat JBoss Enterprise Application Platform Expansion PackRed Hat · Red Hat Single Sign-On 7CVEs relacionadas — Red Hat build of Keycloak 26.4
En el mismo producto, de las más peligrosas a las menos.
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Referencias
https://access.redhat.com/errata/RHSA-2026:50846https://access.redhat.com/errata/RHSA-2026:50847https://access.redhat.com/errata/RHSA-2026:50848https://access.redhat.com/errata/RHSA-2026:50849https://access.redhat.com/security/cve/CVE-2026-16442https://bugzilla.redhat.com/show_bug.cgi?id=2503138