CVE-2026-20009
Estado: AnalizadaMedia (5.3)—
A vulnerability in the implementation of the proprietary SSH stack with SSH key-based authentication in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to log in to a Cisco Secure Firewall ASA device and execute commands as a specific user.
This vulnerability is due to insufficient validation of user input during the SSH authentication phase. An attacker could exploit this vulnerability by submitting crafted input during SSH authentication to an affected device.
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A successful exploit could allow the attacker to log in to the device as a specific user without the private SSH key of that user. To exploit this vulnerability, the attacker must possess a valid username and the associated public key. The private key is not required. Notes:
Detalles técnicos trazas, registros y código del informe original
Exploitation of this vulnerability does not provide the attacker with root access. The authentication, authorization, and accounting (AAA) configuration command auto-enable is not affected by this vulnerability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Puntuación base: 5.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.40%
- Percentil entre todas las CVEs puntuadas: 31
- Fecha de la puntuación: 4/10/2026
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).
Tecnologías afectadas (1)
CWE
- CWE-138
Referencias
JSON original (NVD)
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"value": "A vulnerability in the implementation of the proprietary SSH stack with SSH key-based authentication in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to log in to a Cisco Secure Firewall ASA device and execute commands as a specific user.\r\n\r\nThis vulnerability is due to insufficient validation of user input during the SSH authentication phase. An attacker could exploit this vulnerability by submitting crafted input during SSH authentication to an affected device. A successful exploit could allow the attacker to log in to the device as a specific user without the private SSH key of that user. To exploit this vulnerability, the attacker must possess a valid username and the associated public key. The private key is not required.\r\nNotes:\r\n\r\nExploitation of this vulnerability does not provide the attacker with root access.\r\nThe authentication, authorization, and accounting (AAA) configuration command auto-enable is not affected by this vulnerability. "
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"value": "Una vulnerabilidad en la implementación de la pila SSH propietaria con autenticación basada en clave SSH en el software Cisco Secure Firewall Adaptive Security Appliance (ASA) podría permitir a un atacante remoto no autenticado iniciar sesión en un dispositivo Cisco Secure Firewall ASA y ejecutar comandos como un usuario específico.\n\nEsta vulnerabilidad se debe a una validación insuficiente de la entrada del usuario durante la fase de autenticación SSH. Un atacante podría explotar esta vulnerabilidad al enviar una entrada manipulada durante la autenticación SSH a un dispositivo afectado. Un exploit exitoso podría permitir al atacante iniciar sesión en el dispositivo como un usuario específico sin la clave SSH privada de ese usuario. Para explotar esta vulnerabilidad, el atacante debe poseer un nombre de usuario válido y la clave pública asociada. La clave privada no es necesaria.\nNotas:\n\nLa explotación de esta vulnerabilidad no proporciona al atacante acceso de root.\nEl comando de configuración de autenticación, autorización y contabilidad (AAA) auto-enable no se ve afectado por esta vulnerabilidad."
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"lastModified": "2026-06-17T10:16:52.453",
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