CVE-2025-30385 is a high-severity use-after-free vulnerability (CWE-416) found in the Windows Common Log File System (CLFS) driver on Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability allows an authorized local attacker to elevate privileges by exploiting improper memory management within the CLFS driver. Specifically, the use-after-free condition occurs when the driver accesses memory that has already been freed, potentially enabling an attacker to execute arbitrary code in kernel mode or cause a system crash. The vulnerability requires local access with limited privileges (PR:L) and does not require user interaction (UI:N). The attack complexity is low (AC:L), meaning exploitation is straightforward once local access is obtained. The impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H), indicating that a successful exploit could lead to full system compromise, including unauthorized access to sensitive data, modification of system files, and denial of service. No known exploits are currently reported in the wild, and no patches or mitigations have been officially released at the time of publication (May 13, 2025). The vulnerability is significant because Windows 10 Version 1809 is still in use in various enterprise environments, especially where legacy systems or software compatibility is critical. The CLFS driver is a core component used for logging and system event tracking, so exploitation could undermine system stability and security auditing mechanisms.

For European organizations, this vulnerability poses a serious risk, particularly in sectors relying on Windows 10 Version 1809 for critical infrastructure, manufacturing, healthcare, and government operations. Successful exploitation could allow attackers to gain elevated privileges locally, bypassing security controls and potentially deploying ransomware, stealing sensitive data, or disrupting operations. The high impact on confidentiality, integrity, and availability means that data breaches, system downtime, and loss of trust could result. Organizations with remote or hybrid workforces may face increased risk if attackers gain local access through compromised endpoints or insider threats. Additionally, the lack of a patch at the time of disclosure increases exposure. Compliance with GDPR and other data protection regulations could be jeopardized if this vulnerability is exploited to access personal or sensitive data.

European organizations should immediately identify and inventory all systems running Windows 10 Version 1809. Until an official patch is released, apply the following mitigations: 1) Restrict local access to trusted users only by enforcing strict access controls and monitoring for unauthorized logins. 2) Employ application whitelisting and endpoint detection and response (EDR) solutions to detect anomalous behavior indicative of exploitation attempts. 3) Disable or limit use of the Common Log File System driver where feasible, or isolate critical systems to minimize exposure. 4) Conduct regular system integrity checks and audit logs to detect signs of privilege escalation or tampering. 5) Educate users and administrators about the risks of local privilege escalation vulnerabilities and enforce the principle of least privilege to reduce the attack surface. 6) Prepare for rapid deployment of patches once Microsoft releases an update by testing and validating in controlled environments. 7) Consider upgrading affected systems to a supported and patched Windows version if operationally possible to reduce long-term risk.