Cisco Secure Firewall Adaptive Security Appliance SSH Partial Private Key Authentication Bypass Vulnerability
Published Mar 4, 2026
5.3
MEDIUMCVSS 3.1
EPSS 0.40%
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.
Affected products
-
- Version 9.17.1StatusaffectedConstraints-
- Version 9.17.1.10StatusaffectedConstraints-
- Version 9.17.1.11StatusaffectedConstraints-
- Version 9.17.1.13StatusaffectedConstraints-
- Version 9.17.1.15StatusaffectedConstraints-
- Version 9.17.1.20StatusaffectedConstraints-
- Version 9.17.1.30StatusaffectedConstraints-
- Version 9.17.1.33StatusaffectedConstraints-
- Version 9.17.1.39StatusaffectedConstraints-
- Version 9.17.1.45StatusaffectedConstraints-
- Version 9.17.1.46StatusaffectedConstraints-
- Version 9.17.1.7StatusaffectedConstraints-
- Version 9.17.1.9StatusaffectedConstraints-
- Version 9.18.1StatusaffectedConstraints-
- Version 9.18.1.3StatusaffectedConstraints-
- Version 9.18.2StatusaffectedConstraints-
- Version 9.18.2.5StatusaffectedConstraints-
- Version 9.18.2.7StatusaffectedConstraints-
- Version 9.18.2.8StatusaffectedConstraints-
- Version 9.18.3StatusaffectedConstraints-
- Version 9.18.3.39StatusaffectedConstraints-
- Version 9.18.3.46StatusaffectedConstraints-
- Version 9.18.3.53StatusaffectedConstraints-
- Version 9.18.3.55StatusaffectedConstraints-
- Version 9.18.3.56StatusaffectedConstraints-
- Version 9.18.4StatusaffectedConstraints-
- Version 9.18.4.22StatusaffectedConstraints-
- Version 9.18.4.24StatusaffectedConstraints-
- Version 9.18.4.29StatusaffectedConstraints-
- Version 9.18.4.34StatusaffectedConstraints-
- Version 9.18.4.40StatusaffectedConstraints-
- Version 9.18.4.47StatusaffectedConstraints-
- Version 9.18.4.5StatusaffectedConstraints-
- Version 9.18.4.50StatusaffectedConstraints-
- Version 9.18.4.52StatusaffectedConstraints-
- Version 9.18.4.53StatusaffectedConstraints-
- Version 9.18.4.57StatusaffectedConstraints-
- Version 9.18.4.66StatusaffectedConstraints-
- Version 9.18.4.67StatusaffectedConstraints-
- Version 9.18.4.68StatusaffectedConstraints-
- Version 9.18.4.8StatusaffectedConstraints-
- Version 9.19.1StatusaffectedConstraints-
- Version 9.19.1.12StatusaffectedConstraints-
- Version 9.19.1.18StatusaffectedConstraints-
- Version 9.19.1.22StatusaffectedConstraints-
- Version 9.19.1.24StatusaffectedConstraints-
- Version 9.19.1.27StatusaffectedConstraints-
- Version 9.19.1.28StatusaffectedConstraints-
- Version 9.19.1.31StatusaffectedConstraints-
- Version 9.19.1.37StatusaffectedConstraints-
- Version 9.19.1.38StatusaffectedConstraints-
- Version 9.19.1.42StatusaffectedConstraints-
- Version 9.19.1.5StatusaffectedConstraints-
- Version 9.19.1.9StatusaffectedConstraints-
- Version 9.20.1StatusaffectedConstraints-
- Version 9.20.1.5StatusaffectedConstraints-
- Version 9.20.2StatusaffectedConstraints-
- Version 9.20.2.10StatusaffectedConstraints-
- Version 9.20.2.21StatusaffectedConstraints-
- Version 9.20.2.22StatusaffectedConstraints-
- Version 9.20.3StatusaffectedConstraints-
- Version 9.20.3.10StatusaffectedConstraints-
- Version 9.20.3.13StatusaffectedConstraints-
- Version 9.20.3.16StatusaffectedConstraints-
- Version 9.20.3.20StatusaffectedConstraints-
- Version 9.20.3.4StatusaffectedConstraints-
- Version 9.20.3.7StatusaffectedConstraints-
- Version 9.20.3.9StatusaffectedConstraints-
- Version 9.20.4StatusaffectedConstraints-
- Version 9.20.4.7StatusaffectedConstraints-
- Version 9.22.1.1StatusaffectedConstraints-
- Version 9.22.1.2StatusaffectedConstraints-
- Version 9.22.1.3StatusaffectedConstraints-
- Version 9.22.1.6StatusaffectedConstraints-
- Version 9.22.2StatusaffectedConstraints-
- Version 9.22.2.13StatusaffectedConstraints-
- Version 9.22.2.4StatusaffectedConstraints-
- Version 9.22.2.9StatusaffectedConstraints-
- Version 9.23.1StatusaffectedConstraints-
- Version 9.23.1.13StatusaffectedConstraints-
- Version 9.23.1.3StatusaffectedConstraints-
- Version 9.23.1.7StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
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| Cisco | Cisco Secure Firewall Adaptive Security Appliance (ASA) Software | n/a |
|
- ≥ 9.17.1 · < 9.18.4.71
- ≥ 9.19.1 · < 9.20.4.10
- ≥ 9.22.1.1 · < 9.22.2.14
- ≥ 9.23.1 · < 9.23.1.19
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
YesTechnical Impact
PartialDecision
n/aAssessed Mar 5, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 2, 2026.
Score over time
Mar–Oct 2026- EPSS v4
- EPSS v5
Percentile over time
- EPSS v4
- EPSS v5
Table of values (3 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 0.40% (0.00396) | 31.40th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.38% (0.00381) | 29.65th | v5 (v2026.06.15) |
| Mar 5, 2026 | 0.03% (0.00029) | 8.12th | v4 (v2025.03.14) |
References (1)
Change history (0)
No recorded changes yet.