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CVE-2026-91949

Estado: AnalizadaCrítica (9.2)—

FreeRDP server versions before 3.31.0 contain a protocol negotiation bypass vulnerability that allows unauthenticated attackers to establish RDSTLS connections despite server policy disabling them. Attackers can send incompatible protocol requests, receive negotiation failures, then complete TLS handshake and enter RDSTLS to bypass pre-authentication transport restrictions.

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 negociación de protocolo en servidor FreeRDP expuesto en red sin autenticación (AV:N, PR:N, UI:N). Permite bypass de restricciones preautenticación y acceso RDP no autorizado. CWE-693: improper protocol implementation.

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 ManagementNetwork SegmentationMulti-factor AuthenticationLimit Access to Resource Over NetworkVulnerability ScanningUser Account Management

Tecnologías afectadas (1)

Freerdp — Freerdp

CWE

Referencias

JSON original (NVD)

Mostrar
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