CVE-2025-20029 is an OS command injection vulnerability classified under CWE-78 that affects the F5 BIG-IP product, specifically versions 15.1.0, 16.1.0, and 17.1.0. The vulnerability resides in the iControl REST API and the TMOS Shell (tmsh) save command functionality. An authenticated attacker with low privileges can exploit this flaw to inject and execute arbitrary system commands on the underlying operating system. This occurs due to improper neutralization of special elements in OS commands, allowing malicious input to be interpreted as executable commands. The vulnerability does not require user interaction but does require authentication, which lowers the attack complexity but still poses a significant risk given the privileged nature of the management interfaces. The CVSS 3.1 base score is 8.8, indicating high impact on confidentiality, integrity, and availability. No public exploits have been reported yet, and software versions that have reached End of Technical Support are not evaluated. The vulnerability is critical because BIG-IP devices are widely used for load balancing, application delivery, and security functions in enterprise and service provider networks, making successful exploitation potentially devastating.

Successful exploitation of CVE-2025-20029 can lead to complete system compromise of F5 BIG-IP devices. Attackers could execute arbitrary commands with system-level privileges, potentially allowing them to disrupt network traffic, steal sensitive data, alter configurations, or establish persistent backdoors. This could result in significant downtime, data breaches, and loss of trust in critical network infrastructure. Given the central role of BIG-IP devices in managing and securing network traffic, the impact extends beyond the device itself to the broader enterprise network and connected services. Organizations relying on these devices for application delivery and security enforcement face increased risk of lateral movement and further compromise if this vulnerability is exploited. The absence of known exploits in the wild provides a window for proactive defense, but the high severity score underscores the urgency of mitigation.

1. Apply official patches from F5 as soon as they become available for the affected BIG-IP versions. 2. Restrict access to the iControl REST API and TMOS Shell interfaces to trusted administrators only, using network segmentation, VPNs, or firewall rules. 3. Enforce strong authentication mechanisms and monitor authentication logs for suspicious activity. 4. Implement strict input validation and command filtering where possible in custom integrations interacting with BIG-IP management interfaces. 5. Regularly audit and review BIG-IP configurations and access controls to minimize the attack surface. 6. Employ intrusion detection and prevention systems to detect anomalous command execution attempts. 7. Maintain up-to-date backups and incident response plans to enable rapid recovery in case of compromise. 8. Consider deploying compensating controls such as multi-factor authentication and just-in-time access to reduce risk exposure.