CVE-2025-27492 is a high-severity race condition vulnerability identified in Microsoft Windows Server 2022, specifically version 10.0.20348.0. The flaw exists within the Windows Secure Channel (Schannel) security package, which is responsible for implementing SSL/TLS protocols to secure communications. The vulnerability arises due to improper synchronization when concurrently accessing shared resources, classified under CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization). This race condition can be exploited by an authorized local attacker with low privileges to elevate their privileges on the affected system. The attacker does not require user interaction but must have local access and some level of privileges (low) to trigger the flaw. Exploitation could lead to full compromise of confidentiality, integrity, and availability of the system, as the attacker could gain elevated privileges and potentially execute arbitrary code or disrupt system operations. The CVSS v3.1 base score is 7.0, reflecting high severity, with attack vector local, attack complexity high, privileges required low, no user interaction, unchanged scope, and high impact on confidentiality, integrity, and availability. No known exploits are reported in the wild yet, and no patches have been linked at the time of publication. The vulnerability was reserved in late February 2025 and published in early April 2025. Given the critical role of Windows Server 2022 in enterprise environments, this vulnerability poses a significant risk if exploited.

For European organizations, the impact of CVE-2025-27492 could be substantial. Windows Server 2022 is widely deployed across various sectors including finance, healthcare, government, and critical infrastructure within Europe. Successful exploitation would allow attackers to escalate privileges locally, potentially leading to full system compromise, unauthorized access to sensitive data, disruption of services, and lateral movement within networks. This could result in data breaches violating GDPR regulations, operational downtime, and reputational damage. Since the vulnerability requires local access, it is particularly concerning for environments where multiple users have access to servers or where attackers can gain footholds through other means (e.g., phishing, compromised credentials). The high impact on confidentiality, integrity, and availability means that critical European infrastructure and enterprises relying on Windows Server 2022 could face severe operational and compliance consequences if this vulnerability is exploited.

To mitigate CVE-2025-27492, European organizations should prioritize the following actions: 1) Monitor Microsoft security advisories closely and apply patches immediately once released, as no patches are currently linked. 2) Restrict local access to Windows Server 2022 systems to trusted administrators only, minimizing the number of users with local privileges. 3) Implement strict access controls and use Just-In-Time (JIT) and Just-Enough-Administration (JEA) principles to limit privilege exposure. 4) Employ endpoint detection and response (EDR) solutions to monitor for suspicious local privilege escalation attempts. 5) Conduct regular security audits and vulnerability assessments focusing on privilege escalation vectors. 6) Harden server configurations by disabling unnecessary services and enforcing strong authentication mechanisms. 7) Use application whitelisting and integrity monitoring to detect unauthorized changes. 8) Educate administrators and users about the risks of local privilege escalation and the importance of maintaining secure access practices. These targeted mitigations go beyond generic advice by focusing on minimizing local attack surfaces and preparing for rapid patch deployment.