CVE-2026-20249
A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly.
This vulnerability is due to a logic error during the certificate authentication phase of the IKEv2 connection setup. An attacker could exploit this vulnerability by attempting to establish an IKEv2 VPN connection with a crafted certificate. A successful exploit could allow the attacker to cause the IKEv2 process to crash, causing a denial of service (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: 0.40%
- Percentil entre todas las CVEs puntuadas: 32
- Fecha de la puntuación: 3/10/2026
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 remota sin autenticación (AV:N/PR:N/UI:N) en servicio IKEv2 expuesto; lógica defectuosa permite DoS causando crash del proceso mediante certificado manipulado.
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)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-704
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-20249",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-20249",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-09-18T14:39:33.426532Z"
}
}
],
"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": "9.16.1"
},
{
"status": "affected",
"version": "9.16.1.28"
},
{
"status": "affected",
"version": "9.16.2"
},
{
"status": "affected",
"version": "9.16.2.3"
},
{
"status": "affected",
"version": "9.16.2.7"
},
{
"status": "affected",
"version": "9.16.2.11"
},
{
"status": "affected",
"version": "9.16.2.13"
},
{
"status": "affected",
"version": "9.16.2.14"
},
{
"status": "affected",
"version": "9.16.3.3"
},
{
"status": "affected",
"version": "9.16.3"
},
{
"status": "affected",
"version": "9.16.3.14"
},
{
"status": "affected",
"version": "9.18.1"
},
{
"status": "affected",
"version": "9.16.3.15"
},
{
"status": "affected",
"version": "9.18.1.3"
},
{
"status": "affected",
"version": "9.18.2"
},
{
"status": "affected",
"version": "9.16.3.19"
},
{
"status": "affected",
"version": "9.16.3.23"
},
{
"status": "affected",
"version": "9.18.2.5"
},
{
"status": "affected",
"version": "9.16.4"
},
{
"status": "affected",
"version": "9.18.2.7"
},
{
"status": "affected",
"version": "9.19.1"
},
{
"status": "affected",
"version": "9.16.4.9"
},
{
"status": "affected",
"version": "9.18.2.8"
},
{
"status": "affected",
"version": "9.16.4.14"
},
{
"status": "affected",
"version": "9.18.3"
},
{
"status": "affected",
"version": "9.19.1.5"
},
{
"status": "affected",
"version": "9.16.4.18"
},
{
"status": "affected",
"version": "9.19.1.9"
},
{
"status": "affected",
"version": "9.18.3.39"
},
{
"status": "affected",
"version": "9.16.4.19"
},
{
"status": "affected",
"version": "9.19.1.12"
},
{
"status": "affected",
"version": "9.18.3.46"
},
{
"status": "affected",
"version": "9.16.4.27"
},
{
"status": "affected",
"version": "9.19.1.18"
},
{
"status": "affected",
"version": "9.18.3.53"
},
{
"status": "affected",
"version": "9.18.3.55"
},
{
"status": "affected",
"version": "9.16.4.38"
},
{
"status": "affected",
"version": "9.16.4.39"
},
{
"status": "affected",
"version": "9.18.3.56"
},
{
"status": "affected",
"version": "9.20.1"
},
{
"status": "affected",
"version": "9.16.4.42"
},
{
"status": "affected",
"version": "9.19.1.22"
},
{
"status": "affected",
"version": "9.18.4"
},
{
"status": "affected",
"version": "9.20.1.5"
},
{
"status": "affected",
"version": "9.18.4.5"
},
{
"status": "affected",
"version": "9.19.1.24"
},
{
"status": "affected",
"version": "9.16.4.48"
},
{
"status": "affected",
"version": "9.18.4.8"
},
{
"status": "affected",
"version": "9.20.2"
},
{
"status": "affected",
"version": "9.19.1.27"
},
{
"status": "affected",
"version": "9.16.4.55"
},
{
"status": "affected",
"version": "9.18.4.22"
},
{
"status": "affected",
"version": "9.20.2.10"
},
{
"status": "affected",
"version": "9.16.4.57"
},
{
"status": "affected",
"version": "9.19.1.28"
},
{
"status": "affected",
"version": "9.18.4.24"
},
{
"status": "affected",
"version": "9.20.2.21"
},
{
"status": "affected",
"version": "9.16.4.61"
},
{
"status": "affected",
"version": "9.19.1.31"
},
{
"status": "affected",
"version": "9.18.4.29"
},
{
"status": "affected",
"version": "9.20.2.22"
},
{
"status": "affected",
"version": "9.16.4.62"
},
{
"status": "affected",
"version": "9.18.4.34"
},
{
"status": "affected",
"version": "9.20.3"
},
{
"status": "affected",
"version": "9.16.4.67"
},
{
"status": "affected",
"version": "9.16.4.70"
},
{
"status": "affected",
"version": "9.18.4.40"
},
{
"status": "affected",
"version": "9.23.1"
},
{
"status": "affected",
"version": "9.22.1.1"
},
{
"status": "affected",
"version": "9.16.4.71"
},
{
"status": "affected",
"version": "9.20.3.4"
},
{
"status": "affected",
"version": "9.18.4.47"
},
{
"status": "affected",
"version": "9.20.3.7"
},
{
"status": "affected",
"version": "9.19.1.37"
},
{
"status": "affected",
"version": "9.16.4.76"
},
{
"status": "affected",
"version": "9.20.3.9"
},
{
"status": "affected",
"version": "9.19.1.38"
},
{
"status": "affected",
"version": "9.18.4.50"
},
{
"status": "affected",
"version": "9.22.1.3"
},
{
"status": "affected",
"version": "9.20.3.10"
},
{
"status": "affected",
"version": "9.22.1.2"
},
{
"status": "affected",
"version": "9.18.4.52"
},
{
"status": "affected",
"version": "9.20.3.13"
},
{
"status": "affected",
"version": "9.22.1.6"
},
{
"status": "affected",
"version": "9.18.4.53"
},
{
"status": "affected",
"version": "9.16.4.82"
},
{
"status": "affected",
"version": "9.22.2"
},
{
"status": "affected",
"version": "9.20.3.16"
},
{
"status": "affected",
"version": "9.19.1.42"
},
{
"status": "affected",
"version": "9.18.4.57"
},
{
"status": "affected",
"version": "9.16.4.84"
},
{
"status": "affected",
"version": "9.23.1.3"
},
{
"status": "affected",
"version": "9.20.3.20"
},
{
"status": "affected",
"version": "9.22.2.4"
},
{
"status": "affected",
"version": "9.23.1.7"
},
{
"status": "affected",
"version": "9.20.4"
},
{
"status": "affected",
"version": "9.22.2.9"
},
{
"status": "affected",
"version": "9.23.1.13"
},
{
"status": "affected",
"version": "9.20.4.7"
},
{
"status": "affected",
"version": "9.22.2.13"
},
{
"status": "affected",
"version": "9.18.4.66"
},
{
"status": "affected",
"version": "9.20.4.10"
},
{
"status": "affected",
"version": "9.23.1.19"
},
{
"status": "affected",
"version": "9.16.4.85"
},
{
"status": "affected",
"version": "9.22.2.14"
},
{
"status": "affected",
"version": "9.18.4.67"
},
{
"status": "affected",
"version": "9.24.1"
},
{
"status": "affected",
"version": "9.18.4.68"
},
{
"status": "affected",
"version": "9.23.1.22"
},
{
"status": "affected",
"version": "9.20.4.14"
},
{
"status": "affected",
"version": "9.22.2.20"
},
{
"status": "affected",
"version": "9.18.4.71"
},
{
"status": "affected",
"version": "9.20.4.19"
},
{
"status": "affected",
"version": "9.23.1.26"
},
{
"status": "affected",
"version": "9.16.4.89"
},
{
"status": "affected",
"version": "9.22.2.32"
},
{
"status": "affected",
"version": "9.18.4.76"
},
{
"status": "affected",
"version": "9.22.3"
},
{
"status": "affected",
"version": "9.24.1.5"
},
{
"status": "affected",
"version": "9.20.4.22"
},
{
"status": "affected",
"version": "9.24.1.9"
},
{
"status": "affected",
"version": "9.20.4.28"
},
{
"status": "affected",
"version": "9.16.4.92"
},
{
"status": "affected",
"version": "9.18.4.135"
},
{
"status": "affected",
"version": "9.23.1.195"
},
{
"status": "affected",
"version": "9.20.4.30"
},
{
"status": "affected",
"version": "9.24.1.155"
},
{
"status": "affected",
"version": "9.23.1.32"
},
{
"status": "affected",
"version": "9.18.4.82"
}
],
"defaultStatus": "unknown"
},
{
"vendor": "Cisco",
"product": "Cisco Secure Firewall Threat Defense (FTD) Software",
"versions": [
{
"status": "affected",
"version": "7.0.0"
},
{
"status": "affected",
"version": "7.0.0.1"
},
{
"status": "affected",
"version": "7.0.1"
},
{
"status": "affected",
"version": "7.0.1.1"
},
{
"status": "affected",
"version": "7.0.2"
},
{
"status": "affected",
"version": "7.2.0"
},
{
"status": "affected",
"version": "7.0.2.1"
},
{
"status": "affected",
"version": "7.0.3"
},
{
"status": "affected",
"version": "7.2.0.1"
},
{
"status": "affected",
"version": "7.0.4"
},
{
"status": "affected",
"version": "7.2.1"
},
{
"status": "affected",
"version": "7.0.5"
},
{
"status": "affected",
"version": "7.3.0"
},
{
"status": "affected",
"version": "7.2.2"
},
{
"status": "affected",
"version": "7.2.3"
},
{
"status": "affected",
"version": "7.3.1"
},
{
"status": "affected",
"version": "7.2.4"
},
{
"status": "affected",
"version": "7.0.6"
},
{
"status": "affected",
"version": "7.2.5"
},
{
"status": "affected",
"version": "7.2.4.1"
},
{
"status": "affected",
"version": "7.3.1.1"
},
{
"status": "affected",
"version": "7.4.0"
},
{
"status": "affected",
"version": "7.0.6.1"
},
{
"status": "affected",
"version": "7.2.5.1"
},
{
"status": "affected",
"version": "7.4.1"
},
{
"status": "affected",
"version": "7.2.6"
},
{
"status": "affected",
"version": "7.0.6.2"
},
{
"status": "affected",
"version": "7.4.1.1"
},
{
"status": "affected",
"version": "7.2.7"
},
{
"status": "affected",
"version": "7.2.5.2"
},
{
"status": "affected",
"version": "7.3.1.2"
},
{
"status": "affected",
"version": "7.2.8"
},
{
"status": "affected",
"version": "7.6.0"
},
{
"status": "affected",
"version": "7.4.2"
},
{
"status": "affected",
"version": "7.2.8.1"
},
{
"status": "affected",
"version": "7.0.6.3"
},
{
"status": "affected",
"version": "7.4.2.1"
},
{
"status": "affected",
"version": "7.2.9"
},
{
"status": "affected",
"version": "7.0.7"
},
{
"status": "affected",
"version": "7.7.0"
},
{
"status": "affected",
"version": "7.4.2.2"
},
{
"status": "affected",
"version": "7.2.10"
},
{
"status": "affected",
"version": "7.6.1"
},
{
"status": "affected",
"version": "7.4.2.3"
},
{
"status": "affected",
"version": "7.0.8"
},
{
"status": "affected",
"version": "7.6.2"
},
{
"status": "affected",
"version": "7.7.10"
},
{
"status": "affected",
"version": "7.7.11"
},
{
"status": "affected",
"version": "7.0.8.1"
},
{
"status": "affected",
"version": "7.6.2.1"
},
{
"status": "affected",
"version": "7.7.10.1"
},
{
"status": "affected",
"version": "7.4.2.4"
},
{
"status": "affected",
"version": "7.2.10.2"
},
{
"status": "affected",
"version": "7.4.3"
},
{
"status": "affected",
"version": "7.6.4"
},
{
"status": "affected",
"version": "10.0.0"
},
{
"status": "affected",
"version": "7.4.4"
},
{
"status": "affected",
"version": "7.0.9"
},
{
"status": "affected",
"version": "7.2.11"
},
{
"status": "affected",
"version": "7.4.7"
}
],
"defaultStatus": "unknown"
}
]
}
],
"published": "2026-09-16T21:17:08.517",
"references": [
{
"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-ikev2cert-dos-uWyc2xtv",
"source": "psirt@cisco.com"
}
],
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
{
"type": "Secondary",
"source": "psirt@cisco.com",
"description": [
{
"lang": "en",
"value": "CWE-704"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability in the certification authentication feature of Internet Key Exchange version 2 (IKEv2) for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to reload unexpectedly.\r\n\r\nThis vulnerability is due to a logic error during the certificate authentication phase of the IKEv2 connection setup. An attacker could exploit this vulnerability by attempting to establish an IKEv2 VPN connection with a crafted certificate. A successful exploit could allow the attacker to cause the IKEv2 process to crash, causing a denial of service (DoS) condition."
}
],
"lastModified": "2026-09-18T15:17:06.947",
"sourceIdentifier": "psirt@cisco.com"
}