CVE-2026-20009: Cisco Secure Firewall Adaptive Security Appliance SSH Partial Private Key Authentication Bypass Vulnerability
Cisco · Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
Affected: Cisco Secure Firewall Adaptive Security Appliance (ASA) Software · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 38% of scored CVEs
DescriptionCVE.org
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 products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- Cisco · Cisco Secure Firewall Adaptive Security Appliance (ASA) Software9.17.1; 9.17.1.7; 9.17.1.9; 9.17.1.10; 9.18.1; 9.18.1.3 and 76 more
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- Cisco
- Published
- March 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-20009 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.