CVE-2026-20103
Estado: AnalizadaAlta (8.6)—
A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust device memory resulting in a denial of service (DoS) condition to new Remote Access SSL VPN connections. This does not affect the management interface, though it may become temporarily unresponsive.
This vulnerability is due to trusting user input without validation. An attacker could exploit this vulnerability by sending crafted packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device web interface to stop responding, 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: 27
- 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 %
Vulnerabilidad de aplicación expuesta (VPN SSL remoto accesible sin autenticación, AV:N/PR:N/UI:N) explotable mediante paquetes manipulados. Impacto: agotamiento de memoria causando DoS en servicio de red (T1499.004 - resource exhaustion en endpoint).
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-770
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-20103",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-20103",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-03-04T21:35:44.796593Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 8.6,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 4,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "psirt@cisco.com",
"affectedData": [
{
"vendor": "Cisco",
"product": "Cisco Secure Firewall Adaptive Security Appliance (ASA) Software",
"versions": [
{
"status": "affected",
"version": "9.12.4.48"
},
{
"status": "affected",
"version": "9.12.4.50"
},
{
"status": "affected",
"version": "9.12.4.52"
},
{
"status": "affected",
"version": "9.12.4.54"
},
{
"status": "affected",
"version": "9.12.4.55"
},
{
"status": "affected",
"version": "9.12.4.56"
},
{
"status": "affected",
"version": "9.12.4.58"
},
{
"status": "affected",
"version": "9.12.4.62"
},
{
"status": "affected",
"version": "9.12.4.65"
},
{
"status": "affected",
"version": "9.12.4.67"
},
{
"status": "affected",
"version": "9.16.3.15"
},
{
"status": "affected",
"version": "9.16.3.19"
},
{
"status": "affected",
"version": "9.16.3.23"
},
{
"status": "affected",
"version": "9.16.4"
},
{
"status": "affected",
"version": "9.16.4.9"
},
{
"status": "affected",
"version": "9.16.4.14"
},
{
"status": "affected",
"version": "9.16.4.19"
},
{
"status": "affected",
"version": "9.16.4.27"
},
{
"status": "affected",
"version": "9.16.4.38"
},
{
"status": "affected",
"version": "9.16.4.39"
},
{
"status": "affected",
"version": "9.16.4.42"
},
{
"status": "affected",
"version": "9.16.4.48"
},
{
"status": "affected",
"version": "9.16.4.55"
},
{
"status": "affected",
"version": "9.16.4.57"
},
{
"status": "affected",
"version": "9.16.4.61"
},
{
"status": "affected",
"version": "9.16.4.62"
},
{
"status": "affected",
"version": "9.16.4.67"
},
{
"status": "affected",
"version": "9.16.4.70"
},
{
"status": "affected",
"version": "9.16.4.71"
},
{
"status": "affected",
"version": "9.16.4.76"
},
{
"status": "affected",
"version": "9.16.4.82"
},
{
"status": "affected",
"version": "9.16.4.84"
},
{
"status": "affected",
"version": "9.17.1.20"
},
{
"status": "affected",
"version": "9.17.1.30"
},
{
"status": "affected",
"version": "9.17.1.33"
},
{
"status": "affected",
"version": "9.17.1.39"
},
{
"status": "affected",
"version": "9.17.1.45"
},
{
"status": "affected",
"version": "9.17.1.46"
},
{
"status": "affected",
"version": "9.18.1.3"
},
{
"status": "affected",
"version": "9.18.2"
},
{
"status": "affected",
"version": "9.18.2.5"
},
{
"status": "affected",
"version": "9.18.2.7"
},
{
"status": "affected",
"version": "9.18.2.8"
},
{
"status": "affected",
"version": "9.18.3"
},
{
"status": "affected",
"version": "9.18.3.39"
},
{
"status": "affected",
"version": "9.18.3.46"
},
{
"status": "affected",
"version": "9.18.3.53"
},
{
"status": "affected",
"version": "9.18.3.55"
},
{
"status": "affected",
"version": "9.18.3.56"
},
{
"status": "affected",
"version": "9.18.4"
},
{
"status": "affected",
"version": "9.18.4.5"
},
{
"status": "affected",
"version": "9.18.4.8"
},
{
"status": "affected",
"version": "9.18.4.22"
},
{
"status": "affected",
"version": "9.18.4.24"
},
{
"status": "affected",
"version": "9.18.4.29"
},
{
"status": "affected",
"version": "9.18.4.34"
},
{
"status": "affected",
"version": "9.18.4.40"
},
{
"status": "affected",
"version": "9.18.4.47"
},
{
"status": "affected",
"version": "9.18.4.50"
},
{
"status": "affected",
"version": "9.18.4.52"
},
{
"status": "affected",
"version": "9.18.4.53"
},
{
"status": "affected",
"version": "9.18.4.57"
},
{
"status": "affected",
"version": "9.19.1"
},
{
"status": "affected",
"version": "9.19.1.5"
},
{
"status": "affected",
"version": "9.19.1.9"
},
{
"status": "affected",
"version": "9.19.1.12"
},
{
"status": "affected",
"version": "9.19.1.18"
},
{
"status": "affected",
"version": "9.19.1.22"
},
{
"status": "affected",
"version": "9.19.1.24"
},
{
"status": "affected",
"version": "9.19.1.27"
},
{
"status": "affected",
"version": "9.19.1.28"
},
{
"status": "affected",
"version": "9.19.1.31"
},
{
"status": "affected",
"version": "9.19.1.37"
},
{
"status": "affected",
"version": "9.19.1.38"
},
{
"status": "affected",
"version": "9.19.1.42"
},
{
"status": "affected",
"version": "9.20.1"
},
{
"status": "affected",
"version": "9.20.1.5"
},
{
"status": "affected",
"version": "9.20.2"
},
{
"status": "affected",
"version": "9.20.2.10"
},
{
"status": "affected",
"version": "9.20.2.21"
},
{
"status": "affected",
"version": "9.20.2.22"
},
{
"status": "affected",
"version": "9.20.3"
},
{
"status": "affected",
"version": "9.20.3.4"
},
{
"status": "affected",
"version": "9.20.3.7"
},
{
"status": "affected",
"version": "9.20.3.9"
},
{
"status": "affected",
"version": "9.20.3.10"
},
{
"status": "affected",
"version": "9.20.3.13"
},
{
"status": "affected",
"version": "9.20.3.16"
},
{
"status": "affected",
"version": "9.20.3.20"
},
{
"status": "affected",
"version": "9.22.1.1"
},
{
"status": "affected",
"version": "9.22.1.3"
},
{
"status": "affected",
"version": "9.22.1.2"
},
{
"status": "affected",
"version": "9.22.1.6"
},
{
"status": "affected",
"version": "9.22.2"
},
{
"status": "affected",
"version": "9.22.2.4"
},
{
"status": "affected",
"version": "9.23.1"
},
{
"status": "affected",
"version": "9.23.1.3"
}
]
},
{
"vendor": "Cisco",
"product": "Cisco Secure Firewall Threat Defense (FTD) Software",
"versions": [
{
"status": "affected",
"version": "6.4.0.16"
},
{
"status": "affected",
"version": "6.4.0.17"
},
{
"status": "affected",
"version": "6.4.0.18"
},
{
"status": "affected",
"version": "7.0.4"
},
{
"status": "affected",
"version": "7.0.5"
},
{
"status": "affected",
"version": "7.0.6"
},
{
"status": "affected",
"version": "7.0.6.1"
},
{
"status": "affected",
"version": "7.0.6.2"
},
{
"status": "affected",
"version": "7.0.6.3"
},
{
"status": "affected",
"version": "7.0.7"
},
{
"status": "affected",
"version": "7.0.8"
},
{
"status": "affected",
"version": "7.0.8.1"
},
{
"status": "affected",
"version": "7.1.0.3"
},
{
"status": "affected",
"version": "7.2.1"
},
{
"status": "affected",
"version": "7.2.2"
},
{
"status": "affected",
"version": "7.2.3"
},
{
"status": "affected",
"version": "7.2.4"
},
{
"status": "affected",
"version": "7.2.4.1"
},
{
"status": "affected",
"version": "7.2.5"
},
{
"status": "affected",
"version": "7.2.5.1"
},
{
"status": "affected",
"version": "7.2.6"
},
{
"status": "affected",
"version": "7.2.7"
},
{
"status": "affected",
"version": "7.2.5.2"
},
{
"status": "affected",
"version": "7.2.8"
},
{
"status": "affected",
"version": "7.2.8.1"
},
{
"status": "affected",
"version": "7.2.9"
},
{
"status": "affected",
"version": "7.2.10"
},
{
"status": "affected",
"version": "7.2.10.2"
},
{
"status": "affected",
"version": "7.3.0"
},
{
"status": "affected",
"version": "7.3.1"
},
{
"status": "affected",
"version": "7.3.1.1"
},
{
"status": "affected",
"version": "7.3.1.2"
},
{
"status": "affected",
"version": "7.4.0"
},
{
"status": "affected",
"version": "7.4.1"
},
{
"status": "affected",
"version": "7.4.1.1"
},
{
"status": "affected",
"version": "7.4.2"
},
{
"status": "affected",
"version": "7.4.2.1"
},
{
"status": "affected",
"version": "7.4.2.2"
},
{
"status": "affected",
"version": "7.4.2.3"
},
{
"status": "affected",
"version": "7.4.2.4"
},
{
"status": "affected",
"version": "7.6.0"
},
{
"status": "affected",
"version": "7.6.1"
},
{
"status": "affected",
"version": "7.6.2"
},
{
"status": "affected",
"version": "7.6.2.1"
},
{
"status": "affected",
"version": "7.7.0"
},
{
"status": "affected",
"version": "7.7.10"
},
{
"status": "affected",
"version": "7.7.10.1"
}
]
}
]
}
],
"published": "2026-03-04T18:16:25.840",
"references": [
{
"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-m9sx6MbC",
"tags": [
"Vendor Advisory"
],
"source": "psirt@cisco.com"
}
],
"vulnStatus": "Analyzed",
"weaknesses": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"description": [
{
"lang": "en",
"value": "CWE-770"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability in the Remote Access SSL VPN functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust device memory resulting in a denial of service (DoS) condition to new Remote Access SSL VPN connections. This does not affect the management interface, though it may become temporarily unresponsive. \r\n\r This vulnerability is due to trusting user input without validation. An attacker could exploit this vulnerability by sending crafted packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device web interface to stop responding, resulting in a DoS condition."
},
{
"lang": "es",
"value": "Una vulnerabilidad en la funcionalidad de VPN SSL de Acceso Remoto de Cisco Secure Firewall Adaptive Security Appliance (ASA) Software y Secure Firewall Threat Defense (FTD) Software podría permitir a un atacante remoto no autenticado agotar la memoria del dispositivo, lo que resultaría en una condición de denegación de servicio (DoS) para nuevas conexiones VPN SSL de Acceso Remoto. Esto no afecta la interfaz de gestión, aunque podría dejar de responder temporalmente. Esta vulnerabilidad se debe a confiar en la entrada del usuario sin validación. Un atacante podría explotar esta vulnerabilidad enviando paquetes manipulados al servidor VPN SSL de Acceso Remoto. Un exploit exitoso podría permitir al atacante hacer que la interfaz web del dispositivo deje de responder, lo que resultaría en una condición de DoS."
}
],
"lastModified": "2026-08-11T19:40:47.230",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "74292810-417D-42CC-9123-55166145E91D",
"versionEndExcluding": "9.16.4.85",
"versionStartIncluding": "9.12.1"
},
{
"criteria": "cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "7EFC1809-7619-43ED-80FD-0FC28C876879",
"versionEndExcluding": "9.18.4.66",
"versionStartIncluding": "9.17.1"
},
{
"criteria": "cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "4988A136-196A-448B-A416-992803647AB2",
"versionEndExcluding": "9.20.4",
"versionStartIncluding": "9.19.1"
},
{
"criteria": "cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "55B05CD4-4849-471F-ACC5-0E0478568A2D",
"versionEndExcluding": "9.22.2.4",
"versionStartIncluding": "9.22.1.1"
},
{
"criteria": "cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "61AA6D92-28AC-41E2-8CD3-F7094A079D65",
"versionEndExcluding": "9.23.1.7",
"versionStartIncluding": "9.23.1"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "1D9356BF-153F-46DE-A84C-88C743291468",
"versionEndExcluding": "7.0.9",
"versionStartIncluding": "6.4.0"
},
{
"criteria": "cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F2E5D82E-E596-48CD-AFBB-3FB39F6684A1",
"versionEndExcluding": "7.2.11",
"versionStartIncluding": "7.1.0"
},
{
"criteria": "cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "B3D0EFB8-E018-4732-B99B-9374C1EF602E",
"versionEndExcluding": "7.4.3",
"versionStartIncluding": "7.3.0"
},
{
"criteria": "cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "7C131685-D69C-4460-BFFC-06DA5AD43038",
"versionEndExcluding": "7.6.4",
"versionStartIncluding": "7.6.0"
},
{
"criteria": "cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "491E1C03-FE39-4A29-82B6-85B85494E57D",
"versionEndExcluding": "7.7.11",
"versionStartIncluding": "7.7.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "psirt@cisco.com"
}