Important
Free support for Windows 10 Enterprise LTSC 2021 ends on January 12, 2027. To learn about continuing support, see Plan for Windows 10 Enterprise LTSC 2021 end of support.
Commercial devices running Windows 10, version 22H2 require a Windows 10 Extended Security Updates (ESU) Year 2 license to continue receiving security updates. For more information, see Extended Security Updates (ESU) program for Windows 10.
Summary
This article lists the security issues and quality improvements included in this cumulative security update.
Applies to: Windows 10 ESU
Important
Use EKB KB5015684 to update to Windows 10, version 22H2.
This security update includes fixes and quality improvements that are part of the following updates:
October 26, 2026—KB5134125 (OS Builds 19045.7811 and 19044.7811) Out-of-band
October 13, 2026—KB5126657 (OS Builds 19045.7807 and 19044.7807)
Extended Security Updates (ESU) Licensing Preparation Package for Windows 10
The following is a summary of the issues that this update addresses when you install this update. If there are new features, it lists them as well. The bold text within the brackets indicates the item or area of the change we are documenting.
[Date and Time] This update adjusts daylight saving time (DST) rules for Cuba for the extended 2026-2027 DST period. Cuba remains on UTC-04:00 and doesn't observe the November 2026 and March 2027 transitions. It returns to UTC-05:00 in November 2027 and resumes its regular seasonal schedule in 2028.
- For the latest DST and time zone guidance, see the Daylight Saving Time & Time Zone Blog.
[Printing] - Fixed: Adding a printer published in Active Directory through Settings > Bluetooth & devices > Printers & scanners > Add device might fail with error 87, "The parameter is incorrect." This issue was introduced by the October 2026 update and does not generally affect existing printers or printing.
[Remote Desktop]
- Fixed: The “Specify thumbprints of certificates representing trusted .rdp publishers” policy could not be configured successfully through Microsoft Intune.
- Fixed: Remote Desktop shadow connections might fail with an “Unspecified error” on Windows Server 2016 and Windows Server 2012 R2 after installing the October 14, 2026, update.
[Windows PowerShell] This update strengthens security for PowerShell script signing and signature verification by introducing stricter encoding validation. As a result, scripts containing invalid UTF-8 encoding might fail signature validation, even if they were previously accepted. To resolve this issue, review the affected scripts, save them using valid UTF-8 encoding with a byte order mark (BOM), and sign them again. For further guidance, see Encoding Guidance for Signed PowerShell Scripts.
[Security] This update improves NTLM security by enabling clients to offer NTLM message signing by default for non-anonymous connections. This change helps reduce exposure to NTLM relay attacks and provides auditing to identify connections that are not using signing. To learn more, see NTLM signing security improvements in Windows.
Known issues in this update
USB Audio Class 1.0 devices with error Code 10 or no output
Symptoms
After installing the September 8, 2026, Windows security update, some USB Audio Class 1.0 devices might fail to start or produce audio. Affected devices might experience one or more of the following symptoms:
- The device displays an error in Device Manager: "This device cannot start (Code 10).”
- No audio output.
- Volume controls are unresponsive or remain at zero.
- Sound settings are unresponsive or unavailable.
- Some devices might function in standard stereo configurations but fail when using multichannel audio features, including 8-channel or 3D audio modes. Some customers have reported that they're able to restore audio in these cases by switching to 2-channel mode.
This issue is limited to USB Audio Class 1.0 devices.
Resolution
The symptoms experienced on devices using 8-channel or 3D audio modes are addressed in the out-of-band (OOB) update released on September 14, 2026, (KB5129236). The remaining symptoms are addressed in (KB5131096).
Windows 10 servicing stack update (KB5132689) - version 19041.7838
Microsoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). SSUs improves the reliability of the update process and includes fixes to the servicing stack, the component that installs Windows updates.
Note: This servicing stack update (SSU) includes enhanced logic to verify whether a device is hosted on Azure, leveraging an updated certificate chain for validation. To ensure that the device can access the required certificate update domains to successfully download and install certificate updates, see Certificate downloads and revocation lists and Azure Certificate Authority details. To learn more about SSUs, see Servicing stack updates.
How to get this update
Before you install this update
For Windows Update: You must have the Windows update released on or after July 8, 2025 (such as KB5062554) installed before installing this update.
For Windows Server Update Services (WSUS) deployment or when installing the standalone package from Microsoft Update Catalog: You must have the Windows update released on or after July 8, 2025 (such as KB5062554) installed before installing this update.
For offline OS image servicing: If your image does not have the July 25, 2023 (KB5028244) or later LCU, you must install the special standalone November 10, 2023 SSU (KB5031539) before installing this update.
Servicing Stack Update (SSU): You must have installed servicing stack update version 19044.6088 or later before installing this update. To determine the latest SSU installed on your device, run
DISM /Online /Get-Packages | findstr /i "ServicingStack"from an elevated command prompt. The Package Identity line returned must be version 19044.6088 or later.
Deployment
If you deploy dynamic updates such as this update to an existing Windows image, ensure the boot.stl file is included as part of the installation media. Failure to include the file might prevent devices from successfully starting from the installation media and can result in error code 0xc0430001.
Note
The boot.stl file is used during Secure Boot validation and must match the Windows version and architecture of the image you are updating.
To ensure the boot.stl file is included as part of the installation media, do one of the following:
- Use the Update WinPE script to update an existing Windows image. (Recommended)
- Manually copy the boot.stl file from the devices Windows\Boot\EFI folder to the corresponding folder on your installation media before deploying the update.
For information about how to apply Dynamic Update packages to existing Windows images, see Update Windows installation media with Dynamic Update.
Get and install this update
To get and install this update, use one of the following Windows and Microsoft release channels.
| Available | Next Step |
|---|---|
|
This update will be downloaded and installed automatically from Windows Update. |
File information
A list of the files that are included in this update are provided in a CSV (Comma delimited) (*.csv) file. The file can be opened in a text editor such as Notepad or in Microsoft Excel.
Note The English (United States) version of this software update might contain files for additional languages.
Download the file information for cumulative update KB5131096.
Download the file information for update SSU (KB5132689) - version 19041.7838.
References
For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types.
For an overview of Windows 10, version 21H2 or Windows 10, version 22H2, see its update history page.
Related topics
Microsoft Store application updates
Windows updates do not install Microsoft Store application updates. If you are an enterprise user, see Microsoft Store apps - Configuration Manager. If you are a consumer user, see Get updates for apps and games in Microsoft Store.Secure Boot certificate updates remain in progress as Microsoft transitions devices from certificates that began expiring in 2026 to newer certificates. Devices that have not yet received the newer certificates can continue to start and receive standard Windows updates. Microsoft will continue delivering the newer Secure Boot certificates to eligible devices through Windows Update.