CVE-2026-45657: Windows Kernel Remote Code Execution Vulnerability

Overview

Severity

Critical (CVSS 9.8)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Remote Code Execution

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Jun

Released

2026-06-09

Description

Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.

FAQ

How could an attacker exploit the vulnerability? An attacker could exploit this vulnerability by sending specially crafted network traffic to a vulnerable Windows system. If successful, the malicious network packets could trigger a flaw in how the Windows kernel processes certain TCP/IP data, potentially allowing the attacker to run code with system-level privileges without needing to sign in or interact with a user.

Affected Products (12)

Windows

• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows Server 2025 (Server Core installation)
• Windows 11 Version 25H2 for ARM64-based Systems
• Windows 11 Version 25H2 for x64-based Systems
• Windows 11 Version 23H2 for ARM64-based Systems
• Windows 11 Version 23H2 for x64-based Systems
• Windows 11 Version 24H2 for ARM64-based Systems
• Windows 11 Version 24H2 for x64-based Systems
• Windows Server 2025
• Windows 11 version 26H1 for x64-based Systems
• Windows 11 Version 26H1 for ARM64-based Systems

Security Updates (5)

• 5094128
• 5094125
• 5094126
• 5093998
• 5095051

Acknowledgments

Microsoft

Revision History

• 2026-06-09: Information published.