CVE-2024-30087 is a vulnerability classified under CWE-20 (Improper Input Validation) affecting the Win32k subsystem in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw allows a local attacker with low privileges to escalate their privileges to SYSTEM level by exploiting improper validation of inputs within the Win32k component, which is responsible for graphical device interface and window management functions. This elevation of privilege (EoP) vulnerability does not require user interaction and has a low attack complexity, meaning an attacker with local access can reliably exploit the flaw to gain full control over the affected system. The vulnerability impacts confidentiality, integrity, and availability because an attacker who gains SYSTEM privileges can execute arbitrary code, access sensitive data, and disrupt system operations. Although no public exploits or active exploitation in the wild have been reported yet, the vulnerability is considered high risk due to the critical nature of privilege escalation and the widespread use of Windows 10 1809 in enterprise environments. The vulnerability was reserved in March 2024 and published in June 2024, with no patch links currently available, indicating that organizations must monitor for updates or consider alternative mitigations. The CVSS v3.1 base score is 7.8, reflecting high severity with attack vector local, low complexity, privileges required low, no user interaction, and high impact on confidentiality, integrity, and availability.

For European organizations, this vulnerability poses a significant risk especially to those still operating legacy Windows 10 Version 1809 systems, which are common in industrial control systems, government agencies, and enterprises with long upgrade cycles. Successful exploitation could allow attackers to bypass security controls, gain SYSTEM-level access, and execute arbitrary code, potentially leading to data breaches, ransomware deployment, or disruption of critical services. The impact is heightened in sectors with sensitive data or critical infrastructure, such as finance, healthcare, and public administration. Since the vulnerability requires local access, insider threats or attackers who gain initial foothold through other means (e.g., phishing, remote code execution vulnerabilities) could leverage this flaw to escalate privileges and move laterally within networks. The lack of a current patch increases the window of exposure, making proactive mitigation essential. Additionally, the vulnerability could facilitate advanced persistent threats (APTs) targeting European strategic assets, amplifying geopolitical risks.

1. Prioritize upgrading affected systems from Windows 10 Version 1809 to a supported and patched Windows version to eliminate exposure. 2. Until patches are available, restrict local access to critical systems by enforcing strict access controls, including limiting administrative privileges and using endpoint protection solutions with behavior-based detection. 3. Implement application whitelisting and privilege restriction policies to reduce the attack surface for privilege escalation. 4. Monitor system logs and security telemetry for unusual privilege escalation attempts or suspicious Win32k activity. 5. Employ network segmentation to isolate legacy systems and reduce the risk of lateral movement. 6. Educate IT staff and users about the risks of local privilege escalation and the importance of maintaining updated systems. 7. Prepare incident response plans that include detection and containment strategies for privilege escalation attacks. 8. Regularly review and audit installed Windows versions across the organization to identify and remediate outdated systems.