CVE-2025-62461 is a buffer over-read vulnerability classified under CWE-126, found in the Windows Projected File System Filter Driver component of Microsoft Windows 11 Version 25H2 (build 10.0.26200.0). The flaw allows an authorized local attacker to read beyond the intended buffer boundaries, which can lead to the exposure of sensitive memory contents or cause system instability. This vulnerability can be leveraged to elevate privileges locally, enabling attackers to gain higher-level access rights than initially granted. The attack vector requires local access with low complexity and no user interaction, increasing the risk within environments where multiple users share systems or where attackers have gained limited access. The CVSS v3.1 base score is 7.8, reflecting high severity with impacts rated as high on confidentiality, integrity, and availability. The vulnerability has not been reported as exploited in the wild yet, but its presence in a core Windows component makes it a critical concern. The absence of an official patch at the time of publication necessitates proactive defensive measures. The Projected File System Filter Driver is integral to Windows file system operations, so exploitation could disrupt normal system behavior or leak sensitive data. Organizations should monitor for unusual local privilege escalation attempts and prepare to deploy patches once Microsoft releases them.

For European organizations, this vulnerability poses a significant risk due to the widespread use of Windows 11 in enterprise and government environments. Successful exploitation could lead to unauthorized privilege escalation, allowing attackers to bypass security controls, access sensitive information, and potentially deploy further malicious payloads or ransomware. This could disrupt business operations, compromise personal data protected under GDPR, and damage organizational reputation. Critical sectors such as finance, healthcare, and public administration are particularly vulnerable due to the sensitivity of their data and the potential impact of system compromise. The local attack vector means insider threats or attackers who have gained initial footholds could escalate privileges rapidly. The high integrity and availability impact could lead to system crashes or data corruption, affecting service continuity. Given the lack of known exploits currently, the window for proactive mitigation is open but limited, emphasizing the need for rapid response once patches are available.

1. Restrict local access to systems running Windows 11 Version 25H2 to trusted users only, minimizing the risk of unauthorized local exploitation. 2. Implement strict access controls and monitoring on endpoints to detect unusual privilege escalation attempts or anomalous behavior indicative of exploitation. 3. Employ application whitelisting and endpoint detection and response (EDR) solutions to identify and block suspicious activities related to the Projected File System Filter Driver. 4. Prepare for rapid deployment of official Microsoft patches by maintaining an up-to-date asset inventory and patch management process. 5. Conduct user training to reduce the risk of attackers gaining initial local access through social engineering or credential compromise. 6. Use virtualization or sandboxing for high-risk applications to limit the impact of potential exploits. 7. Regularly audit system logs for signs of buffer over-read exploitation attempts or crashes related to the file system filter driver. 8. Coordinate with Microsoft support channels for early access to patches or mitigation guidance if available.