CVE-2026-66794
A flaw was found in the `cluster-proxy-addon` component of Multicluster Engine for Kubernetes. This vulnerability allows an unauthenticated attacker, who can access the user-facing route, to bypass authentication and authorization checks. By manipulating URL path segments, the attacker can proxy requests to arbitrary services across any managed cluster. This enables unauthorized access to internal services that would otherwise be protected, potentially leading to information disclosure or further compromise of the cluster environment.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
- Puntuación base: 9.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.62%
- Percentil entre todas las CVEs puntuadas: 48
- 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.
- Explotación
T1190Exploit Public-Facing Applicationinitial access95 % - Impacto principal
T1090Proxycommand and control90 % - Impacto secundario
T1005Data from Local Systemcollection80 %
AV:N/PR:N sin interacción permite T1190. El bypass de autenticación y proxy a servicios internos mediante manipulación de rutas (CWE-918 SSRF) indica T1090.primary. Acceso a servicios protegidos implica T1005.secondary para información disclosure.
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
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-918
Referencias
- https://access.redhat.com/errata/RHSA-2026:59556
- https://access.redhat.com/errata/RHSA-2026:59557
- https://access.redhat.com/errata/RHSA-2026:59558
- https://access.redhat.com/errata/RHSA-2026:59559
- https://access.redhat.com/errata/RHSA-2026:59579
- https://access.redhat.com/errata/RHSA-2026:59593
- https://access.redhat.com/security/cve/CVE-2026-66794
- https://bugzilla.redhat.com/show_bug.cgi?id=2507539
JSON original (NVD)
Mostrar
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