CVE-2025-59200 is a race condition vulnerability classified under CWE-362, found in the Data Sharing Service Client component of Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). The flaw arises from improper synchronization when multiple threads or processes concurrently access shared resources, leading to a state where an unauthorized local attacker can perform spoofing attacks. Spoofing here implies that the attacker can impersonate or manipulate data or service responses, potentially misleading other system components or users. The vulnerability requires local access and some user interaction but does not require elevated privileges, making it accessible to a broader range of threat actors with physical or remote desktop access. The CVSS 3.1 vector (AV:L/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L) indicates that the attack vector is local, with low attack complexity, no privileges required, but user interaction is necessary. The scope is changed, meaning the vulnerability can affect resources beyond the initially vulnerable component. Confidentiality impact is low, integrity impact is high, and availability impact is low, suggesting that while data leakage is limited, data or system integrity can be significantly compromised. No patches were linked at the time of publication, and no known exploits in the wild have been reported, but the vulnerability is publicly disclosed and should be considered a high risk. The race condition could allow attackers to manipulate shared data or service responses, potentially leading to privilege escalation or further exploitation chains.

For European organizations, this vulnerability poses a significant risk due to the widespread adoption of Windows 11 25H2 in enterprise environments. The ability of an attacker to spoof locally without privileges can lead to unauthorized actions, data manipulation, or disruption of services, impacting business operations and trustworthiness of systems. Critical sectors such as finance, healthcare, government, and industrial control systems could be targeted to disrupt operations or gain footholds for further attacks. The integrity impact is particularly concerning for environments relying on accurate data sharing and synchronization. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk, especially in scenarios involving insider threats, compromised endpoints, or social engineering. The lack of known exploits currently provides a window for proactive mitigation before active exploitation occurs.

1. Apply official patches from Microsoft immediately once they become available to address the race condition in the Data Sharing Service Client. 2. Restrict local user permissions and enforce the principle of least privilege to minimize the number of users who can interact with vulnerable components. 3. Implement strict endpoint security controls, including application whitelisting and behavior monitoring, to detect suspicious local activities or attempts to exploit race conditions. 4. Educate users about the risks of social engineering and the importance of cautious interaction with prompts or local applications that could trigger the vulnerability. 5. Use advanced logging and monitoring tools to detect anomalies in data sharing service behavior or unexpected synchronization issues. 6. Consider isolating critical systems or using virtualization/containerization to limit the impact of local exploits. 7. Regularly audit and update local access policies and review user accounts to prevent unauthorized local access.