CVE-2025-59200 is a race condition vulnerability classified under CWE-362, affecting the Data Sharing Service Client component in 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 attacker can exploit timing issues to perform spoofing attacks locally. Spoofing here implies that an attacker could impersonate or manipulate data or processes by exploiting the race condition, potentially leading to unauthorized actions or data corruption. The vulnerability requires local access and some user interaction but does not require elevated privileges, increasing its risk profile. 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 needed. The scope is changed, meaning the vulnerability can affect resources beyond the initially vulnerable component. Confidentiality impact is low, but integrity is high, and availability is low, indicating that the attacker can cause significant data or process manipulation but limited data disclosure or system downtime. No patches were linked at the time of publication, and no known exploits are reported in the wild, but the vulnerability is publicly disclosed and should be treated seriously. The race condition nature makes exploitation timing-dependent, but the potential for privilege escalation or lateral movement exists if combined with other vulnerabilities or misconfigurations.

For European organizations, this vulnerability poses a significant risk due to the widespread adoption of Windows 11 25H2 in enterprise environments. The ability for a local attacker to spoof processes or data can lead to unauthorized actions, data integrity compromise, and potential disruption of critical services. Sectors such as finance, healthcare, government, and critical infrastructure are particularly vulnerable because they rely heavily on Windows endpoints and require high data integrity and availability. The changed scope of the vulnerability means that exploitation could affect multiple system components or services beyond the Data Sharing Service Client, potentially amplifying the impact. Although exploitation requires local access and user interaction, insider threats or malware that gains local foothold could leverage this vulnerability to escalate attacks. The lack of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as exploit development may follow public disclosure. European organizations must consider this vulnerability in their risk assessments and incident response planning.

1. Monitor Microsoft security advisories closely and apply official patches or updates for Windows 11 Version 25H2 immediately once available. 2. Until patches are released, restrict local access to sensitive systems by enforcing strict physical and logical access controls, including limiting user permissions and using endpoint protection solutions. 3. Implement application whitelisting and behavior monitoring to detect suspicious local activities that could indicate exploitation attempts. 4. Educate users about the risks of local attacks requiring user interaction to reduce the likelihood of inadvertent exploitation. 5. Employ robust logging and auditing of local process and service activities to identify anomalies related to the Data Sharing Service Client. 6. Consider isolating critical systems or using virtualization/containerization to limit the impact of local exploits. 7. Review and harden synchronization mechanisms and inter-process communication policies where possible, especially in custom or third-party software interacting with Windows services. 8. Integrate this vulnerability into vulnerability management and penetration testing programs to validate mitigation effectiveness.