CVE-2026-41096: Windows DNS Client 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

Unlikely

Patch Tuesday

2026-May

Released

2026-05-12

Description

Heap-based buffer overflow in Microsoft Windows DNS 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 a specially crafted DNS response to a vulnerable Windows system, causing the DNS Client to incorrectly process the response and corrupt memory. In certain configurations, this could allow the attacker to run code remotely on the affected system without authentication.

Affected Products (11)

Windows

• 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 Server 2022, 23H2 Edition (Server Core installation)
• 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 (7)

• 5087539
• 5087423
• 5089549
• 5089466
• 5087420
• 5087541
• 5089548

Acknowledgments

WARP team at Microsoft

Revision History

• 2026-05-12: Information published.