CVE-2026-4636

Estado: ModificadaAlta (8.1)—

A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Puntuación base: 8.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.48%
Percentil entre todas las CVEs puntuadas: 40
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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement85 %
Impacto principalT1078.002 Domain Accountsstealth · persistence · privilege escalation · initial access80 %
Impacto secundarioT1005 Data from Local Systemcollection75 %
Impacto secundarioT1565.002 Transmitted Data Manipulationimpact70 %

Usuario autenticado con rol uma_protection explota validación deficiente (CWE-551) en servicio remoto Keycloak para obtener tokens RPT y acceder a recursos de otros usuarios, escalando permisos sin privilegios adicionales.

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

Privileged Account Management Vulnerability Scanning User Training User Account Management Threat Intelligence Program Password Policies

Tecnologías afectadas (1)

Redhat — Build OF Keycloak

CWE

CWE-551
CWE-551

Referencias

JSON original (NVD)

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