CVE-2025-62464 is a buffer over-read vulnerability classified under CWE-126 affecting the Windows Projected File System (ProjFS) in Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). ProjFS is a component that enables virtualization of file system data, allowing applications to project hierarchical data into the file system namespace. The vulnerability arises from improper validation of memory boundaries when handling ProjFS data structures, leading to an attacker-controlled buffer over-read. This flaw can be exploited by an authorized local attacker with low complexity and no user interaction required to elevate privileges on the affected system. The CVSS v3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. The attacker could leverage this vulnerability to access sensitive information or execute arbitrary code with elevated privileges, potentially compromising the entire system. Although no public exploits or active exploitation have been reported, the vulnerability's nature and ease of exploitation make it a critical concern for organizations using Windows 11 25H2. The vulnerability was reserved in mid-October 2025 and published in early December 2025, indicating recent discovery and disclosure. No patches are currently linked, suggesting that organizations should monitor Microsoft advisories closely for updates. The vulnerability requires local access and privileges but no user interaction, emphasizing the importance of controlling local user permissions and access.

For European organizations, the impact of CVE-2025-62464 could be significant, especially in sectors relying heavily on Windows 11 25H2, such as finance, healthcare, government, and critical infrastructure. Successful exploitation allows local attackers to escalate privileges, potentially leading to full system compromise, unauthorized data access, and disruption of services. This could result in data breaches, operational downtime, and regulatory non-compliance under GDPR and other data protection laws. The vulnerability's ability to affect confidentiality, integrity, and availability simultaneously increases the risk profile. Organizations with large deployments of Windows 11 25H2, particularly those with many local users or shared workstations, face higher exposure. The absence of known exploits currently provides a window for proactive mitigation, but the ease of exploitation and high impact necessitate urgent attention. Additionally, the vulnerability could be leveraged in multi-stage attacks where initial local access is gained through other means, amplifying the threat.

1. Immediately restrict local user privileges to the minimum necessary, avoiding granting administrative rights to standard users. 2. Implement strict access controls and monitoring on systems running Windows 11 25H2 to detect unusual local activity or privilege escalation attempts. 3. Use application whitelisting and endpoint detection and response (EDR) solutions to identify and block suspicious behavior related to ProjFS exploitation. 4. Regularly audit and harden local accounts and services to reduce the attack surface. 5. Prepare for rapid deployment of official patches from Microsoft once released; monitor Microsoft Security Response Center (MSRC) advisories closely. 6. Educate IT staff and users about the risks of local privilege escalation vulnerabilities and enforce policies against unauthorized software installation or execution. 7. Consider network segmentation to limit lateral movement from compromised local accounts. 8. Employ vulnerability scanning tools that can detect the presence of the affected Windows build to prioritize remediation efforts. 9. Maintain up-to-date backups and incident response plans to mitigate potential damage from exploitation.