Executive brief
A security vulnerability has been identified in the Windows Kernel, the core component of the Microsoft Windows operating system. This flaw allows a user who already has basic access to a computer to gain full administrative control over the system. If exploited, an attacker could bypass security restrictions, access sensitive data, or install malicious software that would otherwise be blocked.
Technical details
A use-after-free (UAF) vulnerability exists in the Windows Kernel (CWE-416). The flaw is triggered when the kernel improperly handles objects in memory, allowing an attacker to reuse a memory pointer after it has been freed. To exploit this, an attacker must first have local access to the system with low-level user privileges. Successful exploitation enables the attacker to execute code with elevated privileges, such as SYSTEM, leading to a complete compromise of the host's confidentiality, integrity, and availability. Microsoft has released security updates to address this issue across affected versions of Windows 11 and Windows Server 2025.
Affected products
- Microsoft Windows 11 Version 24H2 10.0.26100.0 to 10.0.26100.8875
- Microsoft Windows 11 Version 25H2 10.0.26200.0 to 10.0.26200.8875
- Microsoft Windows 11 version 26H1 10.0.26100.0 to 10.0.28000.2269
- Microsoft Windows Server 2025 10.0.26100.0 to 10.0.26100.33158
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory