Cisco Firepower Extensible Operating System os command injection

Summaryinfo

A vulnerability was found in Cisco Firepower Extensible Operating System, Secure Firewall Adaptive Security Appliance Software and Unified Computing System. It has been classified as critical. This impacts an unknown function. The manipulation leads to os command injection. This vulnerability is uniquely identified as CVE-2026-20099. Local access is required to approach this attack. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Cisco Firepower Extensible Operating System, Secure Firewall Adaptive Security Appliance Software and Unified Computing System (unknown version). This issue affects an unknown code block. The manipulation with an unknown input leads to a os command injection vulnerability. Using CWE to declare the problem leads to CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2026-20099 since 10/08/2025. The exploitation is known to be easy. Attacking locally is a requirement. Additional levels of successful authentication are required for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 03/07/2026). The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 301137 (Cisco UCS Manager Software Command Injection (cisco-sa-ucsciv-wGYtC78q)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (301137). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Virtualization Software

Vendor

• Cisco

Name

• Firepower Extensible Operating System
• Secure Firewall Adaptive Security Appliance Software
• Unified Computing System

License

• commercial

Website

• Vendor: https://www.cisco.com/

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Be aware that VulDB is the high quality source for vulnerability data.

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