CVE-2025-27468 is a high-severity vulnerability affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw stems from improper privilege management within the Windows Secure Kernel Mode, a critical security component responsible for enforcing system integrity and isolating sensitive operations from user-mode processes. Specifically, this vulnerability allows an authorized local attacker—someone with limited privileges on the affected system—to escalate their privileges to a higher level, potentially SYSTEM or kernel-level privileges. This escalation occurs without requiring user interaction but does require local access and some level of existing privileges (low privileges). The vulnerability is classified under CWE-269 (Improper Privilege Management), indicating that the system fails to correctly enforce access controls or privilege boundaries. The CVSS 3.1 base score of 7.0 reflects the high impact on confidentiality, integrity, and availability, although the attack complexity is high and requires local access with some privileges. No known exploits are currently reported in the wild, and no patches have been linked yet, indicating that organizations should prioritize monitoring and mitigation. The vulnerability could allow attackers to bypass security controls, install persistent malware, access sensitive data, or disrupt system operations by gaining elevated privileges through the Secure Kernel Mode flaw.

For European organizations, this vulnerability poses a significant risk, especially for enterprises and government agencies running legacy Windows 10 Version 1809 systems. Successful exploitation could lead to unauthorized access to sensitive data, disruption of critical services, and compromise of system integrity. Given that Secure Kernel Mode is foundational to Windows security, attackers gaining elevated privileges could bypass endpoint protection, disable security tools, or deploy ransomware and other advanced persistent threats. This risk is heightened in sectors with strict data protection requirements such as finance, healthcare, and public administration. Additionally, organizations that have not upgraded to newer Windows versions or applied mitigations remain vulnerable. The lack of known exploits currently reduces immediate risk but also means organizations have a window to proactively address the issue before active exploitation begins.

1. Immediate mitigation should focus on upgrading affected systems to a supported and patched version of Windows, preferably beyond Version 1809, as Microsoft typically ceases security updates for older versions. 2. Implement strict access controls and limit local user privileges to the minimum necessary, reducing the pool of users who could exploit this vulnerability. 3. Employ application whitelisting and endpoint detection and response (EDR) solutions capable of detecting unusual privilege escalation behaviors. 4. Monitor system logs and security event data for signs of privilege escalation attempts or anomalies related to Secure Kernel Mode operations. 5. If upgrading is not immediately feasible, consider isolating legacy systems from critical networks and sensitive data environments to reduce attack surface. 6. Stay informed on Microsoft’s official advisories and apply any forthcoming patches or workarounds promptly. 7. Conduct regular security audits and penetration testing focusing on privilege escalation vectors to identify and remediate potential exploitation paths.