CVE-2026-20099: Cisco Firepower Extensible Operating System Fxos

Medium severity, CVSS 6.7. EPSS: 0.7% chance of exploitation in the next 30 days.

A vulnerability in the web-based management interface of Cisco FXOS Software and Cisco UCS Manager Software could allow an authenticated, local attacker with administrative privileges to perform command injection attacks on an affected system and elevate privileges to root.  This vulnerability is due to insufficient input validation of command arguments supplied by the user. An attacker could exploit this vulnerability by authenticating to a device and submitting crafted input to the affected command. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system of the affected device with root-level privileges.

Affected products

• Cisco Cisco Firepower Extensible Operating System Fxos: version 2.3.1.99 only; version 2.3.1.56 only; version 2.3.1.110 only; version 2.3.1.58 only; version 2.6.1.174 only; version 2.6.1.157 only; …
• Cisco Cisco Secure Firewall Adaptive Security Appliance ASA Software: version 9.12.2 only; version 9.12.1 only; version 9.12.3 only; version 9.12.4 only; version 9.12.3.2 only; version 9.12.3.12 only; …
• Cisco Cisco Unified Computing System Managed: version 4.0(4h) only; version 4.1(1a) only; version 4.0(1c) only; version 4.0(4a) only; version 4.0(1a) only; version 4.0(1d) only; …

Published 2026-02-25. Last modified 2026-06-17.