IMPORTANT Windows Server 2012 has reached the end of mainstream support and is now in extended support. Starting in July 2020, there will no longer be optional releases (known as "C" or "D" releases) for this operating system. Operating systems in extended support have only cumulative monthly security updates (known as the "B" or Update Tuesday release).
IMPORTANT Starting in July 2020, all Windows Updates will disable the RemoteFX vGPU feature because of a security vulnerability. For more information about the vulnerability, see CVE-2020-1036 and KB4570006. After you install this update, attempts to start virtual machines (VM) that have RemoteFX vGPU enabled will fail, and messages such as the following will appear:
- “The virtual machine cannot be started because all the RemoteFX-capable GPUs are disabled in Hyper-V Manager.”
- “The virtual machine cannot be started because the server has insufficient GPU resources.”
If you re-enable RemoteFX vGPU, a message similar to the following will appear:
- "We no longer support the RemoteFX 3D video adapter. If you are still using this adapter, you may become vulnerable to security risk. Learn more (https://go.microsoft.com/fwlink/?linkid=2131976)”
As of February 11, 2020, Internet Explorer 10 is no longer in support. To get Internet Explorer 11 for Windows Server 2012 or Windows 8 Embedded Standard, see KB4492872. Install one of the following applicable updates to stay updated with the latest security fixes:
Cumulative Update for Internet Explorer 11 for Windows Server 2012.
Cumulative Update for Internet Explorer 11 for Windows 8 Embedded Standard.
The October 2020 Monthly Rollup.
Improvements and fixes
This security update includes improvements and fixes that were a part of update KB4577038 (released previous September 8, 2020) and addresses the following issues:
- Corrects the end date for daylight savings time (DST) in 2021 for the Fiji Islands. For more information, see DST correction in Windows for the Fiji Islands: October 13, 2020.
- Addresses an issue with the Group Policy service that might recursively delete critical files in alphabetic order from %systemroot%\system32. This issue occurs when a policy has been configured to delete cached profiles. These file deletions might cause stop error “0x5A (CRITICAL_SERVICE_FAILED)” boot failures.
- Addresses an issue in which a Null port is created through the user interface.
- Addresses an issue with Microsoft Edge IE Mode that occurs when you enable Configure enhanced hang detection for Internet Explorer mode in Microsoft Edge.
- Security updates to Windows App Platform and Frameworks, Windows Graphics, Windows Shell, Windows Graphics, Windows Silicon Platform, Windows Cloud Infrastructure, Windows Fundamentals, Windows Authentication, Windows Virtualization, Windows Kernel, Windows Core Networking, Windows Network Security and Containers, and Windows SQL components.
For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.
Known issues in this update
|Certain operations, such as rename, that you perform on files or folders that are on a Cluster Shared Volume (CSV) may fail with the error, “STATUS_BAD_IMPERSONATION_LEVEL (0xC00000A5)”. This occurs when you perform the operation on a CSV owner node from a process that doesn’t have administrator privilege.|| |
Do one of the following:
Microsoft is working on a resolution and will provide an update in an upcoming release.
How to get this update
Before installing this update
We strongly recommend that you install the latest servicing stack update (SSU) for your operating system before installing the latest Rollup. SSUs improve the reliability of the update process to mitigate potential issues while installing the Rollup and applying Microsoft security fixes. For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.
Install this update
|Release Channel||Available||Next Step|
|Windows Update and Microsoft Update||Yes||None. This update will be downloaded and installed automatically from Windows Update.|
|Microsoft Update Catalog||Yes||To get the standalone package for this update, go to the Microsoft Update Catalog website.|
|Windows Server Update Services (WSUS)||Yes|| |
This update will automatically sync with WSUS if you configure Products and Classifications as follows:
Product: Windows Server 2012, Windows Embedded 8 StandardClassification: Security Updates
For a list of the files that are provided in this update, download the file information for update 4580382.