CVE-2026-67192
Xlight FTP Server before 3.9.5 contains a pre-authentication stack buffer overflow vulnerability that allows unauthenticated attackers to corrupt stack memory by sending malformed SSH packets when a GCM cipher is negotiated. Attackers can craft packets with an unvalidated length field passed directly to the GCM decrypt function, overwriting the stack cookie and return address to potentially achieve remote code execution before any authentication occurs.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/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: 9.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.03%
- Percentil entre todas las CVEs puntuadas: 62
- 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
T1059Command and Scripting Interpreterexecution90 %
Vulnerabilidad de desbordamiento de búfer previa a autenticación en servicio FTP SSH expuesto en red (AV:N, PR:N). Permite ejecución remota de código (stack overflow + RCE potencial) sin autenticación.
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-121
Referencias
JSON original (NVD)
Mostrar
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