Update KB5013943 fixes screen flickering and problems with .NET apps on Windows 11

Microsoft has just rolled out update KB5013943 for Windows 11 with security updates, improvements, and fixes for screen flickering in Safe Mode and an issue that prevented some .NET 3.5 applications from opening.

KB5013943 is a required cumulative update because it contains the May 2022 Patch Tuesday security updates for vulnerabilities discovered in previous months.

Windows 11 users can install this update by going to Settings > Windows Update and clicking the Check for Update button. Alternatively, you can also download update KB5013943 through the Microsoft Update Catalog.

What's New in Windows 11 Update KB5013943?

After installing update KB5013943, the Windows 11 version number will change to 22000.675.

KB5013943 includes about 27 improvements and bug fixes, 5 notable issues fixed are listed below:

1. Microsoft fixed an issue that prevented .NET Framework 3.5 applications from opening. Only applications that used Windows Communication Foundation (WCF) and Windows Workflow (WWF) components will experience this issue.
2. Microsoft has fixed an issue that causes your screen to flicker if you start Windows in Safe Mode.
3. Microsoft fixed an issue that caused video subtitles to be partially cropped or incorrectly aligned.
4. If you align your taskbar to the left, Windows 11 will display the temperature above the weather icon.
5. The minimize, maximize and close buttons should now work as expected when using an application window.

New zero-day vulnerability patch in all versions of Windows

In the May 2022 Patch Tuesday update, Microsoft also addressed the Windows LSA spoofing zero-day vulnerability that is being actively exploited. An attacker could abuse this vulnerability to exploit remotely to force domain controllers to authenticate them through the Windows NT LAN Manager (NTLM) security protocol.

LSA (short for Local Security Authority) is a protected subsystem of Windows whose task is to enforce local security policies and authenticate local and remote login users.

The new vulnerability is tracked under code CVE-2022-26925 and reported by Raphael John of Bertelsmann Printing Corporation. It can generate a new attack vector for the PetitPotam NTLM campaign.

CVE-2022-26925 affects all versions of Windows, including client and server platforms, starting with Windows 7 and Windows Server 2008 through to Windows 11 and Windows Server 2022.

Besides CVE-2022-26925, Microsoft also patched two other vulnerabilities including Windows Hyper-V Denial of Service (CVE-2022-22713) and Magnitude Simba Amazon Redshift ODBC Driver (CVE-2022-29972) in Patch Tuesday update May 2022.