CVE-2025-24985 is an integer overflow vulnerability classified under CWE-190, found in the Windows Fast FAT Driver component of Microsoft Windows 10 Version 1507 (build 10.0.10240.0). The flaw arises when the driver improperly handles integer values during file system operations involving the FAT file system, leading to an integer overflow or wraparound condition. This can cause memory corruption, enabling an attacker with local access to execute arbitrary code with system privileges. The vulnerability does not require prior authentication or elevated privileges but does require user interaction, such as opening a specially crafted file or media. The CVSS v3.1 score of 7.8 indicates a high severity due to the potential for full system compromise affecting confidentiality, integrity, and availability. No public exploits have been reported yet, but the vulnerability is publicly disclosed and documented by Microsoft and CISA. The affected Windows 10 version is an early release (1507), which is largely out of mainstream support, increasing the risk for legacy systems that remain unpatched. The vulnerability highlights the risks associated with legacy file system drivers and the importance of maintaining updated operating systems.

The impact of CVE-2025-24985 is significant for organizations still running Windows 10 Version 1507, especially those relying on FAT file systems or handling removable media formatted with FAT. Successful exploitation allows an attacker to execute arbitrary code locally, potentially leading to full system compromise. This can result in unauthorized data access, modification, or destruction, as well as disruption of critical services. Since the vulnerability affects confidentiality, integrity, and availability, it poses a comprehensive threat. Organizations with legacy systems in industrial control environments, healthcare, government, or financial sectors may face increased risk due to the critical nature of their operations and the potential for lateral movement within networks. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk in environments where insider threats or social engineering are possible. The lack of known exploits currently reduces immediate risk but does not preclude future exploitation attempts.

To mitigate CVE-2025-24985, organizations should first identify and inventory systems running Windows 10 Version 1507. Since this version is outdated, the primary recommendation is to upgrade to a supported and patched version of Windows 10 or later. If upgrading is not immediately feasible, restrict local access to affected systems by enforcing strict access controls and limiting user permissions. Disable or restrict the use of FAT file systems where possible, especially on removable media, to reduce the attack surface. Employ endpoint protection solutions capable of detecting anomalous behavior related to file system drivers. Educate users about the risks of opening untrusted files or media to reduce the likelihood of user interaction exploitation. Monitor system logs and alerts for suspicious activity related to file system operations. Stay informed about any patches or security advisories released by Microsoft and apply them promptly once available. Implement application whitelisting and least privilege principles to minimize the impact of potential exploitation.