CVE-2026-16442

Estado: AnalizadaCrítica (9.8)—

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

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.31%
Percentil entre todas las CVEs puntuadas: 22
Fecha de la puntuación: 5/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access80 %

Vulnerabilidad remota sin autenticación (AV:N, PR:N, UI:N) en endpoint SAML que permite bypass de restricciones de acceso. El atacante con control de identidad upstream se autentica ilegítimamente (T1078.001) y manipula la federación (T1556.003, modificación de autenticación).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability Scanning Privileged Account Management Password Policies Network Segmentation Multi-factor Authentication Limit Access to Resource Over Network

Tecnologías afectadas (1)

Redhat — Build OF Keycloak

CWE

CWE-346

Referencias

JSON original (NVD)

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