CVE-2026-20009
Vulnérabilité moyenne dans Cisco Secure Firewall Adaptive Security Appliance (ASA) Software (Cisco)
Description
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. 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: 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.
Gravité et risque d'exploitation
CVE-2026-20009 obtient un score CVSS de 5.3/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.40 %, ce qui la place devant 32.3 % des CVE référencées.
Que faire ?
- Vérifiez si Cisco Secure Firewall Adaptive Security Appliance (ASA) Software (versions 9.17.1.13, 9.18.4.8, 9.20.2.10, 9.19.1.9, 9.23.1.3, 9.19.1.18, 9.19.1.27, 9.17.1.9, 9.19.1.37, 9.23.1.13, 9.20.3.7, 9.20.3.10, 9.18.4.29, 9.18.3.56, 9.18.4.67, 9.18.4.24, 9.18.3.55, 9.17.1.7, 9.18.4.22, 9.20.3.9, 9.22.1.1, 9.22.2.13, 9.17.1.33, 9.17.1, 9.18.4.53, 9.19.1.42, 9.22.1.3, 9.19.1.38, 9.18.1.3, 9.22.2.9, 9.18.4.66, 9.20.1.5, 9.17.1.10, 9.18.2, 9.18.3, 9.20.1, 9.18.4, 9.17.1.39, 9.17.1.20, 9.20.2, 9.17.1.11, 9.20.3.13, 9.18.2.8, 9.22.2, 9.18.3.53, 9.18.1, 9.23.1, 9.20.4.7, 9.19.1.22, 9.18.4.68, 9.20.3.16, 9.18.4.34, 9.18.4.47, 9.18.4.52, 9.20.4, 9.18.2.5, 9.17.1.46, 9.17.1.45, 9.19.1.28, 9.20.3, 9.17.1.15, 9.19.1.24, 9.18.3.39, 9.19.1, 9.22.1.6, 9.17.1.30, 9.23.1.7, 9.18.4.40, 9.20.3.20, 9.20.2.21, 9.18.2.7, 9.20.3.4, 9.22.1.2, 9.22.2.4, 9.19.1.5, 9.18.3.46, 9.19.1.31, 9.20.2.22, 9.18.4.50, 9.19.1.12, 9.18.4.5, 9.18.4.57) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.