CVE-2026-20039
Estado: AnalizadaAlta (8.6)—
A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
This vulnerability is due to ineffective memory management of the VPN web server. An attacker could exploit this vulnerability by sending a large number of crafted HTTP requests to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- Puntuación base: 8.6
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.36%
- Percentil entre todas las CVEs puntuadas: 28
- 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).
🎯 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
T1499.004Application or System Exploitationimpact90 %
Vector CVSS AV:N/PR:N/UI:N indica explotación remota sin privilegios (T1190). Envío de HTTP requests crafted causa recarga del dispositivo (DoS/T1499.004). CWE-244 confirma gestión deficiente de recursos.
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 (2)
CWE
- CWE-244
Referencias
JSON original (NVD)
Mostrar
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"published": "2026-03-04T18:16:17.140",
"references": [
{
"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-dos-SpOFF2Re",
"tags": [
"Vendor Advisory"
],
"source": "psirt@cisco.com"
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"vulnStatus": "Analyzed",
"weaknesses": [
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"type": "Secondary",
"source": "psirt@cisco.com",
"description": [
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}
]
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],
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"lang": "en",
"value": "A vulnerability in the VPN web server of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.\r\n\r\nThis vulnerability is due to ineffective memory management of the VPN web server. An attacker could exploit this vulnerability by sending a large number of crafted HTTP requests to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition."
},
{
"lang": "es",
"value": "Una vulnerabilidad en el servidor web VPN de Cisco Secure Firewall Adaptive Security Appliance (ASA) Software y Cisco Secure Firewall Threat Defense (FTD) Software podría permitir a un atacante remoto no autenticado causar una condición de denegación de servicio (DoS) en un dispositivo afectado.\n\nEsta vulnerabilidad se debe a una gestión de memoria ineficaz del servidor web VPN. Un atacante podría explotar esta vulnerabilidad enviando un gran número de solicitudes HTTP manipuladas a un dispositivo afectado. Un exploit exitoso podría permitir al atacante provocar que el dispositivo se reinicie, lo que resultaría en una condición de DoS."
}
],
"lastModified": "2026-08-11T19:40:47.230",
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