Microsoft released its monthly Patch Tuesday updates on March 10, 2026, bringing important security fixes and reliability improvements for Windows 11 users. Two cumulative updates are included in this rollout: KB5079473 for Windows 11 versions 24H2 and 25H2, and KB5078883 for Windows 11 version 23H2.

These updates address 83 security vulnerabilities, improve system reliability, and continue the gradual rollout of new Secure Boot certificates, which will replace the certificates originally introduced in 2011. Here’s a complete overview of what’s included in the March 2026 Windows updates.

Which Windows 11 Versions Receive the Update?

The KB5079473 cumulative update targets systems running Windows 11 24H2 and 25H2. After installation, the operating system will move to the following build numbers:

• Build 26100.8037 for Windows 11 24H2
• Build 26200.8037 for Windows 11 25H2

Meanwhile, users running Windows 11 23H2 receive update KB5078883, which upgrades the system to build 22631.6783.

These updates are distributed automatically through Windows Update, though manual installation is also possible via the Microsoft Update Catalog.

March 2026 Patch Tuesday Fixes 83 Security Vulnerabilities

Security remains the main focus of this month’s Patch Tuesday. Microsoft has patched 83 vulnerabilities across Windows components and services.

Additionally, 10 non-Microsoft CVEs were republished, mainly related to the Microsoft Edge browser.

The good news is that none of the vulnerabilities are currently known to be actively exploited, meaning there are no confirmed zero-day attacks addressed in this update.

However, several high-severity vulnerabilities were fixed, including:

• A critical vulnerability in the Python SDK of the Semantic Kernel, rated 9.9 on the CVSS scale.
• Multiple vulnerabilities rated 8.8 affecting important services such as:
  • Print Spooler
  • Active Directory
  • Routing and Remote Access Service (RRAS)
  • Microsoft SharePoint
  • Microsoft SQL Server

Microsoft also flagged five vulnerabilities as “Exploitation More Likely.” These impact key system components, including:

• Windows Kernel
• Winlogon
• Server Message Block (SMB)
• Windows accessibility infrastructure

Because these vulnerabilities could potentially be exploited in the future, installing the update promptly is strongly recommended.

Reliability Improvements and System Fixes

In addition to security patches, the March updates include several reliability improvements across Windows 11.

Improvements for Windows 11 24H2 and 25H2

One of the key improvements focuses on File Explorer search reliability. Users previously reported inconsistent search behavior when:

• Searching across multiple drives
• Searching directly from “This PC”

This update improves indexing and search stability to deliver more consistent results.

Microsoft also fixed an issue related to Windows Defender Application Control (WDAC). Under certain endpoint security policies, COM objects could be incorrectly blocked when the endpoint security policy level exceeded the authorization policy. The update resolves this conflict.

Another change affects the Windows System Image Manager, which now displays a confirmation dialog when selecting catalog files. This ensures that files originate from trusted sources before they are used.

Improvements for Windows 11 23H2

The KB5078883 update introduces additional stability fixes.

One major improvement targets GPU stability, particularly in situations such as:

• Shutting down the device
• Running intensive workloads
• Playing modern video games
• Using 3D rendering applications

Microsoft also fixed an issue with File History, the built-in Windows backup tool. Previously, backup operations could fail when files contained Chinese characters in their names. The update restores compatibility with these filenames.

Secure Boot Certificate Transition Continues

Another important part of this update concerns Secure Boot, a critical security feature designed to prevent unauthorized software from running during system startup.

The certificates currently used by Secure Boot date back to 2011 and are scheduled to expire in June 2026. To prevent potential boot issues, Microsoft has started a gradual transition to new certificates.

With the March Patch Tuesday update:

• More devices become eligible to receive the new Secure Boot certificates.
• Deployment remains conditional and staged.

Microsoft only installs the new certificates on systems that demonstrate sufficient update reliability signals. This careful rollout strategy helps avoid compatibility problems on certain hardware configurations.

New PowerShell Commands for Secure Boot Management

The KB5078883 update for Windows 11 23H2 also introduces two new PowerShell commands to help administrators manage Secure Boot more easily.

1. Display Secure Boot Certificates

Get-SecureBootUEFI -Decoded

This command displays Secure Boot keys and certificates in a human-readable format, making it easier to audit firmware security.

2. Check Secure Boot Security Version Number

Get-SecureBootSVN

This command retrieves the Security Version Number (SVN) for the device’s UEFI firmware and boot loader, helping administrators verify system integrity.

How to Install the March 2026 Windows Updates

The updates KB5079473 and KB5078883 are available through Windows Update and are installed automatically if automatic updates are enabled.

To Check for Updates Manually

1. Press Win + I to open Settings.
2. Navigate to Windows Update.
3. Click Check for updates.

If available, Windows will download and install the update automatically.

For manual installation, both updates are also available through the Microsoft Update Catalog, which is often used by IT administrators managing multiple systems.

Conclusion

The March 2026 Patch Tuesday brings important security fixes and stability improvements for Windows 11. By addressing 83 vulnerabilities, improving File Explorer reliability, stabilizing GPU performance, and continuing the Secure Boot certificate transition, Microsoft reinforces both security and long-term system stability.

Even though no vulnerabilities are currently being exploited, several high-severity issues were resolved, making it strongly advisable to install these updates as soon as possible. Keeping your system updated remains one of the most effective ways to protect your device and ensure optimal Windows performance.