CVE-2025-55223 is a race condition vulnerability classified under CWE-362, found in the Graphics Kernel component of Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This flaw arises from improper synchronization when multiple threads or processes concurrently access shared resources, leading to a race condition. An authorized local attacker can exploit this vulnerability to elevate privileges by manipulating the timing of resource access, potentially gaining SYSTEM-level rights. The vulnerability impacts confidentiality, integrity, and availability, as elevated privileges can allow unauthorized data access, system modification, or denial of service. The attack complexity is high, requiring precise timing and local access with low privileges, but no user interaction is needed. Although no public exploits or patches are currently available, the vulnerability is officially published and rated with a CVSS 3.1 score of 7.0, indicating a high severity level. The absence of a patch necessitates immediate mitigation through access control and monitoring. The vulnerability specifically affects Windows 10 Version 1809, a legacy OS version still in use in some environments, particularly in enterprise and industrial contexts. Exploitation could be leveraged in targeted attacks against organizations relying on this OS version, especially where local user accounts have limited restrictions.

For European organizations, the impact of CVE-2025-55223 can be significant, particularly in sectors where Windows 10 Version 1809 remains operational, such as manufacturing, healthcare, government, and critical infrastructure. Successful exploitation allows local attackers to escalate privileges to SYSTEM level, potentially leading to full system compromise, data breaches, unauthorized access to sensitive information, and disruption of critical services. This could undermine confidentiality, integrity, and availability of affected systems. Given the high attack complexity and requirement for local access, the threat is more relevant in environments with multiple users or where attackers can gain initial footholds through other means (e.g., phishing or insider threats). The lack of a patch increases the risk window, making proactive defense essential. Organizations with legacy systems or delayed patch cycles are particularly vulnerable. The threat also poses risks to supply chains and interconnected networks within Europe, potentially cascading impacts across multiple organizations.

1. Restrict local user permissions to the minimum necessary, especially on Windows 10 Version 1809 systems, to reduce the risk of local privilege escalation. 2. Implement strict application whitelisting and endpoint protection to detect and block suspicious local activities that may attempt to exploit race conditions. 3. Employ system hardening practices, including disabling unnecessary services and limiting access to the Graphics Kernel subsystem where feasible. 4. Monitor system logs and security events for anomalies indicative of race condition exploitation attempts, such as unusual process behavior or privilege escalations. 5. Isolate legacy Windows 10 1809 systems from critical network segments and limit remote access to reduce attack surface. 6. Prepare for patch deployment by tracking Microsoft updates closely and testing patches in controlled environments once available. 7. Conduct regular security awareness training focusing on local threat vectors and insider risks. 8. Consider upgrading affected systems to supported Windows versions with ongoing security updates to eliminate exposure to this vulnerability.