CVE-2026-20016: Input Validation

Published Mar 4, 2026
·
Updated

A vulnerability in the Cisco FXOS Software CLI feature for Cisco Secure Firewall ASA Software and Secure FTD Software could allow an authenticated, local attacker to execute arbitrary commands on the underlying operating system with root-level privileges. To exploit this vulnerability, the attacker must have valid administrative credentials on an affected device. This vulnerability is due to insufficient input validation of user-supplied command arguments. An attacker could exploit this vulnerability by submitting crafted input for specific CLI commands. A successful exploit could allow the attacker to execute commands on the underlying operating system with root-level privileges.

Affected Software

13 affected components
Cisco FXOS Software
Cisco Secure Firewall ASA Software
Cisco Secure FTD Software
Cisco Adaptive Security Appliance Software>=9.12.1<9.16.4.85
Cisco Adaptive Security Appliance Software>=9.17.1<9.18.4.66
Cisco Adaptive Security Appliance Software>=9.19.1<9.20.4
Cisco Adaptive Security Appliance Software>=9.22.1.1<9.22.2.4
Cisco Adaptive Security Appliance Software>=9.23.1<9.23.1.7
Cisco Secure Firewall Threat Defense>=6.4.0<7.0.9
Cisco Secure Firewall Threat Defense>=7.1.0<7.2.11
Cisco Secure Firewall Threat Defense>=7.3.0<7.4.3
Cisco Secure Firewall Threat Defense>=7.6.0<7.6.4
Cisco Secure Firewall Threat Defense>=7.7.0<7.7.11

Event History

Mar 4, 2026
CVE Published
via MITRE·06:34 PM
Data Sourced
via MITRE·06:34 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·07:16 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2026-20016?

CVE-2026-20016 is considered a critical severity vulnerability due to its potential to allow authenticated attackers to execute arbitrary commands with root privileges.

2

How do I fix CVE-2026-20016?

To fix CVE-2026-20016, it is recommended to apply the latest patches and updates provided by Cisco for the affected software.

3

Who is affected by CVE-2026-20016?

CVE-2026-20016 affects users of Cisco FXOS Software, Cisco Secure Firewall ASA Software, and Cisco Secure FTD Software.

4

What can an attacker do with CVE-2026-20016?

An attacker exploiting CVE-2026-20016 can execute arbitrary commands on the underlying operating system, leading to potential system compromise.

5

Is CVE-2026-20016 being actively exploited?

As of now, there have been no public reports indicating active exploitation of CVE-2026-20016, but it is advisable to remediate it promptly.

Contact

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