Executive brief
A security vulnerability has been identified in the Windows Kernel, the core component of the Microsoft Windows operating system. This flaw allows an individual who already has basic access to a computer to gain full administrative control. Such an exploit could be used by attackers to bypass security restrictions, access sensitive data, or install persistent malicious software.
Technical details
A heap-based buffer overflow vulnerability exists in the Windows Kernel due to a numeric truncation error (CWE-197). The flaw is triggered when the kernel improperly handles memory allocation during specific operations, leading to a buffer overflow (CWE-122). An attacker with low-privileged local access can exploit this vulnerability without any user interaction to execute code in kernel mode. Successful exploitation grants the attacker SYSTEM privileges, allowing for full compromise of the affected host. Microsoft has released security updates to address this issue across various versions of Windows and Windows Server.
Affected products
- Microsoft Windows 10 1607, 1809, 21H2, 22H2
- Microsoft Windows 11 24H2, 25H2, 26H1
- Microsoft Windows Server 2012 All editions
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory