CVE-2025-54116 is a high-severity vulnerability classified under CWE-284 (Improper Access Control) affecting Microsoft Windows 10 Version 1809, specifically build 10.0.17763.0. The vulnerability resides in Windows MultiPoint Services, a feature designed to enable multiple users to simultaneously share one computer, commonly used in educational and enterprise environments. The flaw allows an authorized attacker with limited privileges to locally elevate their privileges, potentially gaining higher-level access than intended. The CVSS 3.1 base score of 7.3 reflects a high severity, with the vector indicating that the attack requires local access (AV:L), low attack complexity (AC:L), and privileges already present but limited (PR:L). User interaction is required (UI:R), and the scope remains unchanged (S:U). The impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H), meaning successful exploitation can lead to full system compromise, data theft, or disruption. No known exploits are currently reported in the wild, and no patches have been linked yet, suggesting that mitigation may rely on vendor updates or workarounds once available. The vulnerability’s improper access control nature means that the system fails to enforce correct permission checks, allowing privilege escalation from a lower-privileged user to higher privileges, which could be exploited to execute arbitrary code or access sensitive information.

For European organizations, this vulnerability poses a significant risk, especially in sectors relying on Windows 10 Version 1809 in environments where MultiPoint Services is deployed, such as educational institutions, government offices, and enterprises using shared computing resources. Successful exploitation could allow attackers to bypass security controls, leading to unauthorized access to sensitive data, disruption of services, or lateral movement within networks. Given the high impact on confidentiality, integrity, and availability, organizations could face data breaches, operational downtime, and compliance violations under regulations like GDPR. The requirement for local access and user interaction somewhat limits remote exploitation but does not eliminate risk, as insider threats or malware that gains initial foothold could leverage this vulnerability to escalate privileges and deepen compromise.

Organizations should prioritize upgrading or patching affected systems once Microsoft releases an official fix. In the interim, practical mitigations include disabling Windows MultiPoint Services if not required, restricting local user permissions to the minimum necessary, and enforcing strict user account control policies to limit privilege escalation opportunities. Monitoring and logging local user activities can help detect suspicious attempts to exploit privilege escalation. Employing endpoint protection solutions with behavioral detection capabilities may also help identify exploitation attempts. Additionally, organizations should ensure that all users follow the principle of least privilege and that multi-factor authentication is enforced for sensitive accounts to reduce the risk of initial compromise that could lead to exploitation of this vulnerability.