CVE-2025-6543

Estado: AnalizadaCrítica (9.2)⚠ Explotación activa

Memory overflow vulnerability leading to unintended control flow and Denial of Service in NetScaler ADC and NetScaler Gateway when configured as Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/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: 9.2

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 11%
Percentil entre todas las CVEs puntuadas: 96
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).

CISA KEV — explotada activamente

Añadida al catálogo: 30/6/2025
Plazo de remediación: 21/7/2025
Uso conocido en ransomware: Unknown

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1059 Command and Scripting Interpreterexecution75 %
Impacto secundarioT1499.004 Application or System Exploitationimpact80 %

Buffer overflow (CWE-119) en servicio remoto expuesto (AV:N, PR:N) permite RCE o DoS; NetScaler es aplicación web/gateway accesible remotamente, encaja T1190. Impacto: ejecución de código (T1059) o denegación de servicio (T1499.004).

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 Management Filter Network Traffic Vulnerability Scanning Restrict Web-Based Content Network Segmentation Limit Software Installation

Tecnologías afectadas (2)

Citrix — Netscaler Application Delivery Controller Citrix — Netscaler Gateway

CWE

CWE-119

Referencias

JSON original (NVD)

Mostrar

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