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CVE-2026-67294

Estado: AnalizadaCrítica (9.3)—

FreeRDP before 3.29.0 improperly validates the Extended Key Usage (EKU) purpose of the peer certificate during client-side server TLS authentication. In x509_utils_verify(), when server-purpose (X509_PURPOSE_SSL_SERVER) verification fails, the code falls back to client-purpose and any-purpose verification, so a trusted, hostname-matching certificate valid only for clientAuth can be accepted as the RDP server certificate. In environments relying on EKU separation between client and server certificates, this allows a clientAuth-only certificate issued by a trusted CA to bypass server certificate purpose validation.

CVSS

Probabilidad de explotación (EPSS)

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.

Vulnerabilidad de validación de certificados TLS en FreeRDP (AV:N, PR:N, UI:N) permite a atacante en red inyectar certificado clientAuth para suplantar servidor RDP y capturar credenciales (MITM/impersonación).

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

User TrainingPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkFilter Network TrafficApplication Developer Guidance

Tecnologías afectadas (1)

Freerdp — Freerdp

CWE

Referencias

JSON original (NVD)

Mostrar
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    }
  ],
  "lastModified": "2026-09-11T21:03:16.017",
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