CVE-2026-9087

Estado: ModificadaAlta (8.1)—

A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.

CVSS

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

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.39%
Percentil entre todas las CVEs puntuadas: 31
Fecha de la puntuación: 6/10/2026

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.

ExplotaciónT1203 Exploitation for Client Executionexecution75 %
Impacto principalT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access80 %
Impacto secundarioT1098.001 Additional Cloud Credentialspersistence · privilege escalation70 %

UI:R (requiere interacción del usuario) indica T1203. El atacante engaña al usuario para que valide una sesión de prueba cross-session, permitiendo vincular una segunda cuenta upstream a la cuenta local de la víctima, obteniendo acceso no autorizado (T1078.001) y manipulación de cuentas (T1098.001).

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

Multi-factor Authentication User Account Management Privileged Account Management Password Policies Network Segmentation Disable or Remove Feature or Program

Tecnologías afectadas (1)

Redhat — Build OF Keycloak

CWE

CWE-639

Referencias

JSON original (NVD)

Mostrar

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