A significant security flaw has been identified in WatchGuard’s Firebox firewall appliances, potentially allowing remote, unauthenticated attackers to execute arbitrary code on affected systems. This vulnerability, designated as CVE-2025-9242, carries a critical severity rating with a Common Vulnerability Scoring System (CVSS) score of 9.3 out of 10. WatchGuard disclosed this issue in advisory WGSA-2025-00015, released on September 17, 2025, and has provided patches to address the vulnerability.
Technical Details:
The vulnerability originates from an out-of-bounds write error within the `iked` process of WatchGuard’s Fireware OS. The `iked` process manages the Internet Key Exchange (IKE) protocol, which is essential for establishing secure Virtual Private Network (VPN) connections. An attacker can exploit this flaw by sending specially crafted data packets to a vulnerable device without requiring authentication. Successful exploitation could lead to arbitrary code execution, potentially resulting in full control over the firewall. This control may allow attackers to intercept network traffic, gain unauthorized access to internal networks, or disrupt security operations.
Affected Configurations and Versions:
The vulnerability specifically impacts Firebox devices running certain versions of Fireware OS configured with specific VPN setups. The primary affected configurations include:
– Mobile User VPN with IKEv2
– Branch Office VPN using IKEv2 with a dynamic gateway peer
Notably, even if these configurations have been removed, a Firebox may remain vulnerable if it was previously set up with one of these VPN types and still maintains an active branch office VPN to a static gateway peer.
The affected Fireware OS versions are:
– 11.10.2 up to 11.12.4_Update1
– 12.0 up to 12.11.3
– 2025.1 release
Mitigation and Recommendations:
WatchGuard has released patched versions of Fireware OS to address CVE-2025-9242. Administrators are strongly encouraged to upgrade their devices to the following versions promptly:
– 2025.1.1
– 12.11.4
– 12.5.13 (for T15 & T35 models)
– 12.3.1_Update3 (for the FIPS-certified release)
For organizations unable to apply the updates immediately, a temporary workaround is available. This involves implementing WatchGuard’s security best practices for securing branch office VPNs that use IPSec and IKEv2, particularly when configured with static gateway peers. However, applying the official patches remains the most effective method to fully mitigate the risk posed by this critical vulnerability.
Broader Implications:
This vulnerability underscores the importance of regular security assessments and timely patch management in maintaining the integrity of network security devices. Firewalls serve as the first line of defense against external threats; thus, vulnerabilities within these systems can have far-reaching consequences. Organizations should prioritize the following actions:
1. Regular Software Updates: Ensure that all network security devices are running the latest firmware versions to benefit from security patches and enhancements.
2. Configuration Audits: Regularly review and audit firewall configurations to identify and rectify any settings that may expose the network to vulnerabilities.
3. Network Monitoring: Implement continuous monitoring solutions to detect and respond to unusual network activities promptly.
4. Incident Response Planning: Develop and maintain an incident response plan to address potential security breaches effectively.
Conclusion:
The discovery of CVE-2025-9242 in WatchGuard’s Firebox firewalls highlights the critical need for vigilance in cybersecurity practices. Organizations must act swiftly to apply the necessary patches and review their network configurations to prevent potential exploitation. By adopting proactive security measures and staying informed about emerging threats, organizations can enhance their resilience against cyber attacks.
