Junglewise Threat Intelligence

CVE-2026-45657: Microsoft Windows Kernel use after free remote code execution

CVE-2026-45657 · Severity: critical · CVSS 9.8 · Published 2026-06-09

Technologies: Microsoft Windows. Vendors: Microsoft.

Executive brief

A critical vulnerability has been identified in the Windows operating system kernel, which manages the core operations of the computer. This flaw allows a remote attacker to gain full control over a system without needing any user interaction or login credentials. An exploit could lead to a total compromise of the affected server or workstation, resulting in data theft, service disruption, or the installation of malware.

Technical details

This vulnerability is classified as a Use-After-Free (CWE-416) and Heap-based Buffer Overflow (CWE-122) within the Windows Kernel. The flaw is triggered when the kernel improperly handles objects in memory, allowing an attacker to send specially crafted network packets to a vulnerable system. Because the vulnerability exists at the kernel level and is reachable over the network without authentication (AV:N/AC:L/PR:N/UI:N), a successful exploit grants the attacker SYSTEM-level privileges. This can lead to full remote code execution (RCE). Microsoft has released security updates to address this issue via the MSRC.

Affected products

  • Microsoft Windows All supported versions

Timeline

  • 2026-06-09: disclosed
  • 2026-06-09: advisory

References