Cisco Secure Firewall Adaptive Security Appliance SSH Partial Private Key Authentication Bypass Vulnerability (Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.44 % · percentile 38 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- cisco
- NVD status
- Analyzed
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.
Weaknesses (CWE)
- CWE-138 — Improper Neutralization of Special Elements
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N | cisco |
| CVSS 3.1 | MEDIUM 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N | NVD · psirt@cisco.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-9429
- GCVE · GCVE-0-2026-20009
Affected configurations (NVD CPE)
cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*≥ 9.17.1 < 9.18.4.71cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*≥ 9.19.1 < 9.20.4.10cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*≥ 9.22.1.1 < 9.22.2.14cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*≥ 9.23.1 < 9.23.1.19
Affected products
| Product | Versions |
|---|---|
| Cisco · Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | affected 9.17.1 ; affected 9.17.1.7 ; affected 9.17.1.9 ; affected 9.17.1.10 ; affected 9.18.1 ; affected 9.18.1.3 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |