CVE-2025-54111 is a high-severity use-after-free vulnerability affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw exists in the Windows UI XAML Phone DatePickerFlyout component, where improper handling of memory leads to a use-after-free condition. This vulnerability allows a locally authorized attacker with low privileges to execute a privilege escalation attack, potentially gaining higher system privileges. The vulnerability does not require user interaction but does require local access and elevated complexity to exploit due to the high attack complexity rating. The vulnerability impacts confidentiality, integrity, and availability, as successful exploitation could allow an attacker to execute arbitrary code with elevated privileges, modify system settings, or disrupt system operations. The CVSS 3.1 base score is 7.8, reflecting the high impact and moderate exploitability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability is classified under CWE-416 (Use After Free), a common memory corruption issue that can lead to arbitrary code execution if exploited correctly.

For European organizations, this vulnerability poses a significant risk especially to enterprises and government entities still running Windows 10 Version 1809, which is an older but still in-use OS version in some environments. Exploitation could lead to unauthorized privilege escalation, allowing attackers to bypass security controls, access sensitive data, or disrupt critical services. This is particularly concerning for sectors with high-value targets such as finance, healthcare, and critical infrastructure. The local attack vector means that attackers would need initial access, which could be gained through other means such as phishing or insider threats, making it a potential component in multi-stage attacks. The lack of user interaction requirement increases the risk of automated or stealthy exploitation once local access is obtained. The vulnerability could also be leveraged in targeted attacks against organizations with legacy systems that have not been updated or patched, increasing the attack surface in European enterprises.

Organizations should prioritize upgrading or patching affected Windows 10 Version 1809 systems as soon as official patches become available from Microsoft. In the interim, restricting local access to trusted users only and enforcing strict access controls can reduce the risk of exploitation. Employing application whitelisting and endpoint detection and response (EDR) solutions can help detect anomalous behavior indicative of exploitation attempts. Regularly auditing systems to identify legacy OS versions and planning migration to supported Windows versions will reduce exposure. Additionally, implementing the principle of least privilege for user accounts and disabling unnecessary local accounts can limit the potential for privilege escalation. Monitoring system logs for unusual activity related to the DatePickerFlyout component or memory corruption events may provide early warning signs of exploitation attempts.