CVE-2025-59200 is a race condition vulnerability classified under CWE-362 that affects the Data Sharing Service Client component in Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). This vulnerability arises from improper synchronization when multiple threads or processes concurrently access shared resources, leading to inconsistent or unexpected behavior. Specifically, an unauthorized local attacker can exploit this flaw to perform spoofing attacks, potentially impersonating legitimate processes or users by manipulating the timing of resource access. The vulnerability requires local access and some user interaction but does not require elevated privileges, making it accessible to standard users or malicious insiders. The CVSS 3.1 base score of 7.7 (AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L) indicates that while the attack vector is local and requires user interaction, the impact on integrity is high, with partial confidentiality and availability impacts, and the vulnerability affects system-wide scope due to the shared resource nature. No public exploits have been reported yet, but the vulnerability is published and should be addressed promptly. The race condition could allow attackers to bypass security controls, inject malicious data, or disrupt normal operations, posing risks to data integrity and system reliability. This vulnerability is particularly concerning for environments where multiple processes or users rely on the Data Sharing Service Client for inter-process communication or data exchange.

For European organizations, this vulnerability poses a significant risk to the confidentiality, integrity, and availability of systems running Windows 11 Version 25H2. Attackers with local access could exploit the race condition to spoof legitimate processes or users, potentially leading to unauthorized data access, privilege escalation, or disruption of critical services. This is especially impactful for sectors such as finance, healthcare, government, and critical infrastructure, where data integrity and system availability are paramount. The requirement for local access and user interaction limits remote exploitation but raises concerns about insider threats and compromised endpoints. The vulnerability could facilitate lateral movement within networks or enable attackers to bypass security mechanisms, increasing the risk of broader compromise. Given the widespread adoption of Windows 11 in European enterprises, the potential attack surface is substantial. The partial impact on confidentiality and high impact on integrity could lead to data manipulation or leakage, undermining trust and compliance with regulations such as GDPR. Availability impact, though low, could still disrupt business continuity if exploited in critical systems.

Organizations should prioritize deploying official patches from Microsoft as soon as they become available to address this race condition vulnerability. Until patches are released, restrict local access to systems running Windows 11 Version 25H2 by enforcing strict physical and logical access controls, including the use of endpoint protection solutions that monitor for anomalous local activity. Implement application whitelisting and least privilege principles to limit the ability of unauthorized users to execute or interact with the Data Sharing Service Client. Conduct regular audits of user accounts and local access logs to detect suspicious behavior indicative of exploitation attempts. Employ advanced endpoint detection and response (EDR) tools capable of identifying race condition exploitation patterns or unusual inter-process communications. Educate users about the risks of local exploitation and the importance of not executing untrusted code or interacting with suspicious prompts. Network segmentation can help contain potential lateral movement resulting from local compromise. Finally, maintain up-to-date backups and incident response plans to quickly recover from any exploitation consequences.