A heap-based buffer overflow vulnerability in the Windows Kernel allows a local, authenticated attacker to gain elevated privileges on affected Windows 11 and Windows Server 2025 systems.

This is a heap-based buffer overflow (CWE-122) occurring within the Windows Kernel. The vulnerability requires the attacker to be authenticated with low privileges to trigger the flaw locally.

The ability for a low-privileged user to escalate to higher privileges poses a severe risk to system integrity and confidentiality. Given the CVSS score of 7.8, this vulnerability is classified as High severity, as it enables an attacker to bypass standard security boundaries and gain full control over the operating system.

Immediate Action: Apply the February 2026 Microsoft security updates immediately to all affected Windows 11 and Windows Server 2025 installations.

Proactive Monitoring: Monitor system logs for unusual process creation or unauthorized attempts to access sensitive kernel-level resources.

Compensating Controls: Ensure that the principle of least privilege is enforced and restrict local login capabilities to untrusted users to limit the attack surface.

Public Exploit Available: No (exploit_available: false)

This high-severity vulnerability represents a significant risk to host security. Administrators should prioritize the deployment of the vendor-supplied security patches across all identified Windows environments to remediate this privilege escalation vector. Failure to patch may allow attackers who have gained initial access to escalate their permissions, leading to full system compromise.