Windows DHCP Client Denial of Service Vulnerability

Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely CVE-2026-118739 · score 6.5/10

What could go wrong?

An attacker could make a program or service crash or stop responding.

How urgent is it?

Check Microsoft’s page for details.

Who is affected?

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

What should I do?

Install this month’s updates via Windows Update, Intune or your update tool, then restart.

Known problems

Microsoft lists known issues per update: KB5121003, KB5120994, KB5120233, KB5120228, KB5121000. Official page.