Executive brief
A security vulnerability exists in the Windows NTFS file system, which is the primary system used by Windows to store and retrieve files on hard drives. An attacker who already has basic access to a computer could exploit this flaw to run malicious code with higher privileges, potentially taking full control of the system. This could lead to the theft of sensitive data, installation of malware, or disruption of business operations.
Technical details
A heap-based buffer overflow vulnerability (CWE-122) exists within the Windows NTFS driver. The flaw is triggered when the system improperly handles memory allocation during file system operations. An attacker with low-privileged local access can exploit this vulnerability, though it requires some level of user interaction as indicated by the CVSS UI:R vector. Successful exploitation allows for local code execution with elevated privileges. Microsoft has released security updates to address this issue across multiple versions of Windows 10 and Windows 11.
Affected products
- Microsoft Windows 10 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 23H2, 24H2, 25H2, 26H1
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory: Microsoft released security update guide.