CVE-2026-40033

Estado: ModificadaAlta (8.7)—

FreeRDP before 3.26.0 contains a heap-buffer-overflow vulnerability in gdi_CacheToSurface that allows remote attackers to write out-of-bounds heap memory. The vulnerability occurs because rectangle validation clamps coordinates to UINT16_MAX but performs copy operations using unclamped cache entry dimensions, enabling malicious RDP servers to trigger large out-of-bounds writes and potentially achieve remote code execution or client crash.

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Puntuación base: 8.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 1.06%
Percentil entre todas las CVEs puntuadas: 63
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.

ExplotaciónT1203 Exploitation for Client Executionexecution95 %
Impacto principalT1059 Command and Scripting Interpreterexecution75 %
Impacto secundarioT1499.004 Application or System Exploitationimpact80 %

Vector CVSS indica UI:P (interacción del usuario necesaria) y AV:N (red): explotación en cliente remoto T1203. Heap-buffer-overflow en FreeRDP permite RCE (T1059) o crash DoS (T1499.004). VC:H/VI:H/VA:H confirman impacto crítico.

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

Restrict Web-Based Content Privileged Account Management Limit Software Installation Filter Network Traffic Execution Prevention Behavior Prevention on Endpoint

Tecnologías afectadas (1)

Freerdp — Freerdp

CWE

CWE-122
CWE-787

Referencias

JSON original (NVD)

Mostrar

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