KB5075943 — February 2026 Security Hotpatch for Windows Server 2022

Overview

KB5075943 is a critical security hotpatch update released on February 10, 2026, for Windows Server 2022 systems. This update advances the operating system build to 20348.4711 and addresses multiple high-priority security vulnerabilities without requiring a system restart. The hotpatch technology allows production servers to receive critical security fixes while maintaining continuous operation and minimizing service disruption.

Security Vulnerabilities Addressed

This hotpatch update resolves several categories of security vulnerabilities that could potentially compromise Windows Server 2022 systems:

Remote Code Execution Vulnerabilities

The update patches critical remote code execution flaws in Windows Server components that could allow attackers to execute arbitrary code on target systems. These vulnerabilities affect core server services, networking components, and system libraries. The fixes implement enhanced input validation, improved memory handling, and strengthened security boundaries to prevent exploitation.

Privilege Escalation Issues

Several elevation of privilege vulnerabilities in the Windows kernel are addressed by this hotpatch. These flaws could allow local attackers to gain SYSTEM-level access and compromise server security. The fixes include improved privilege checks, enhanced access control mechanisms, and corrected security boundaries in kernel-mode components.

Information Disclosure Vulnerabilities

The update resolves information disclosure vulnerabilities in the Windows networking stack that could expose sensitive server information to unauthorized parties. These fixes implement proper memory initialization, enhanced data sanitization, and improved network protocol handling to prevent information leakage.

Authentication Security Enhancements

Security bypass vulnerabilities in Windows authentication mechanisms are patched, including improvements to Kerberos authentication, NTLM protocol handling, and certificate validation processes. These enhancements prevent attackers from bypassing authentication controls and gaining unauthorized access to server resources.

Affected Systems

KB5075943 applies to the following Windows Server 2022 configurations:

Hotpatch Technology Benefits

This update utilizes Microsoft's hotpatch technology, which provides several advantages for production server environments:

• Zero Downtime: Security fixes are applied without requiring a system restart
• Continuous Operation: Server services remain available during update installation
• Reduced Maintenance Windows: Eliminates the need for scheduled downtime for security updates
• Improved Security Posture: Faster deployment of critical security fixes

Installation Requirements

Before installing KB5075943, ensure the following requirements are met:

System Prerequisites

• Windows Server 2022 with current servicing stack update
• Administrative privileges for installation
• Minimum 500 MB available disk space
• Active Windows Update service

Network Requirements

• Internet connectivity for Windows Update (if using automatic updates)
• Access to WSUS server (for enterprise deployments)
• Firewall rules allowing Windows Update traffic

Deployment Methods

Organizations can deploy KB5075943 using various methods depending on their infrastructure and requirements:

Automatic Windows Update

The hotpatch is automatically delivered to Windows Server 2022 systems with automatic updates enabled. Installation begins immediately upon download completion.

Manual Installation

Download the standalone package from Microsoft Update Catalog for manual installation using the following command:

wusa.exe KB5075943-x64.msu /quiet /norestart

Enterprise Deployment

Use Windows Server Update Services (WSUS) or Microsoft Endpoint Configuration Manager to deploy the hotpatch across multiple servers in a controlled manner.

Verification and Monitoring

After installation, verify the hotpatch was applied successfully:

Get-HotFix -Id KB5075943

Check the current OS build number:

[System.Environment]::OSVersion.Version

The build number should show 20348.4711 after successful installation.

Security Impact Assessment

The vulnerabilities addressed by KB5075943 are classified as critical and important severity levels. Without this update, Windows Server 2022 systems remain vulnerable to:

• Remote code execution attacks targeting server components
• Local privilege escalation attempts
• Information disclosure through network protocols
• Authentication bypass techniques
• Denial of service attacks against server services

Organizations should prioritize the deployment of this hotpatch to maintain security compliance and protect against known vulnerabilities.