Executive brief
A security vulnerability exists in the Windows file system (NTFS) that could allow a user with basic access to a computer to gain full administrative control. By exploiting this flaw, an attacker who already has a way to run simple commands on a machine can bypass security restrictions to access sensitive data or install malicious software. This affects a wide range of Windows operating systems, including Windows 10, Windows 11, and Windows Server.
Technical details
A stack-based buffer overflow vulnerability (CWE-121) exists in the Windows NTFS file system driver. The flaw is triggered when the driver improperly handles specific data structures, allowing an attacker to overwrite memory on the program stack. To exploit this, an attacker must first have local access to the system and the ability to execute code with low-level user privileges. Successful exploitation allows the attacker to execute arbitrary code with SYSTEM privileges, leading to a full compromise of the affected host. Microsoft has released security updates to address this issue across supported versions of Windows and Windows Server.
Affected products
- Microsoft Windows 10 Versions 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 Versions 24H2, 25H2, 26H1
- Microsoft Windows Server 2012 All editions including Server Core
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory: Microsoft released security update guide details