CVE-2025-12026 is an out-of-bounds write vulnerability classified under CWE-787 found in the certificate request command of WatchGuard Fireware OS. This vulnerability affects multiple versions of Fireware OS, specifically versions 12.0 up to 12.11.4, 12.5 up to 12.5.13, and 2025.1 up to 2025.1.2. The flaw allows an authenticated user with privileged access to execute arbitrary code by sending specially crafted commands via the command-line interface (CLI). The vulnerability does not require user interaction and can be exploited remotely over the network, as indicated by the CVSS vector (AV:N/AC:L/PR:H/UI:N). The attack complexity is low, meaning an attacker with privileged credentials can reliably exploit this issue without additional conditions. The impact metrics show high confidentiality, integrity, and availability impacts, meaning successful exploitation could lead to full system compromise, data breaches, or denial of service. Although no public exploits are known at this time, the severity and ease of exploitation make this a critical concern for organizations relying on WatchGuard Fireware OS for network security. The lack of available patches at the time of publication necessitates immediate risk mitigation and monitoring. The vulnerability arises from improper bounds checking during the processing of certificate request commands, leading to memory corruption and potential arbitrary code execution.

For European organizations, this vulnerability poses a significant risk to network security infrastructure, especially those using WatchGuard Fireware OS as a firewall or VPN gateway. Exploitation could allow attackers with privileged access to gain full control over affected devices, leading to unauthorized data access, interception of network traffic, disruption of services, or pivoting to other internal systems. Critical sectors such as finance, healthcare, government, and telecommunications could face severe operational and reputational damage. The high confidentiality and integrity impact could result in data breaches involving sensitive personal or corporate information, potentially violating GDPR and other data protection regulations. Availability impact could disrupt business continuity and critical services. Since exploitation requires privileged authentication, insider threats or compromised credentials are primary risk vectors. However, the network attack vector and low complexity mean that once credentials are obtained, exploitation is straightforward. The absence of known exploits currently provides a window for proactive defense, but the risk of future exploitation remains high.

1. Immediately restrict CLI access to Fireware OS devices to only trusted administrators and enforce strong authentication mechanisms such as multi-factor authentication (MFA). 2. Monitor and audit CLI command usage closely to detect any unusual or unauthorized certificate request commands. 3. Implement network segmentation to limit access to Fireware OS management interfaces from untrusted networks. 4. Prepare for rapid deployment of vendor patches once released; maintain close communication with WatchGuard for updates. 5. Use host-based intrusion detection systems (HIDS) and network intrusion detection systems (NIDS) to identify potential exploitation attempts. 6. Conduct regular credential audits and enforce strict password policies to reduce the risk of credential compromise. 7. Consider temporary compensating controls such as disabling the certificate request command if feasible without impacting operations. 8. Train administrators on the risks of this vulnerability and the importance of secure management practices. 9. Maintain up-to-date backups and incident response plans to quickly recover from potential compromises.