CVE-2025-62221 is a use-after-free vulnerability classified under CWE-416, found in the Windows Cloud Files Mini Filter Driver component of Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This component is responsible for managing cloud file synchronization and caching, enabling seamless access to cloud-stored files as if they were local. The vulnerability arises when the driver improperly handles memory, freeing an object but continuing to use the dangling pointer, which can lead to arbitrary code execution or system corruption. An attacker with authorized local access but limited privileges can exploit this flaw to elevate their privileges to SYSTEM level, thereby gaining full control over the affected system. The CVSS v3.1 base score is 7.8, reflecting high severity due to the combination of local attack vector, low attack complexity, required privileges, and no user interaction needed. The impact includes full compromise of confidentiality, integrity, and availability of the system. Although no known exploits are currently reported in the wild, the vulnerability's nature makes it a significant risk for environments running this outdated Windows version. The lack of a patch link indicates that remediation may still be pending or in progress. Organizations relying on Windows 10 Version 1809 should prepare to deploy updates promptly and consider interim mitigations to limit local access and monitor for exploitation attempts.

For European organizations, this vulnerability poses a substantial risk, particularly for enterprises and public sector entities still operating Windows 10 Version 1809. Successful exploitation allows attackers to escalate privileges locally, potentially leading to full system compromise, data breaches, and disruption of critical services. Confidentiality is at risk as attackers could access sensitive data; integrity is compromised through unauthorized code execution or system modifications; availability could be affected if attackers disrupt system operations. The threat is especially concerning for organizations with high-value targets such as financial institutions, healthcare providers, and government agencies. The lack of user interaction requirement and low complexity of exploitation increase the likelihood of internal threat actors or malware leveraging this vulnerability. Given the extended support lifecycle of Windows 10 and the prevalence of this version in some sectors, the impact could be widespread if not addressed promptly.

1. Apply official Microsoft security updates as soon as they become available for Windows 10 Version 1809 to remediate the vulnerability. 2. Until patches are deployed, restrict local user access to systems running this version, especially limiting administrative and privileged accounts. 3. Implement strict access controls and monitoring on endpoints to detect unusual activity related to the Cloud Files Mini Filter Driver or privilege escalation attempts. 4. Use endpoint detection and response (EDR) tools to identify exploitation behaviors and contain compromised systems quickly. 5. Consider upgrading affected systems to a more recent, supported Windows version with active security updates to reduce exposure. 6. Conduct regular audits of local user privileges and remove unnecessary accounts to minimize attack surface. 7. Educate IT staff and users about the risks of local privilege escalation vulnerabilities and the importance of timely patching. 8. Employ application whitelisting and exploit mitigation technologies such as Control Flow Guard (CFG) to hinder exploitation.