July 13, 2021—KB5004285 (Security-only update)
Release Date:
13/07/2021
Version:
Security-only update
Important: This release includes the Flash Removal Package. Taking this update will remove Adobe Flash from the device. For more information, see the Update on Adobe Flash Player End of Support.
Important: Windows 8.1 and Windows Server 2012 R2 have reached the end of mainstream support and are now in extended support. Starting in July 2020, there will no longer be optional, non-security releases (known as "C" releases) for this operating system. Operating systems in extended support have only cumulative monthly security updates (known as the "B" or Update Tuesday release).article. To view other notes and messages, see the Windows 8.1 and Windows Server 2012 R2 update history home page.
For information about the various types of Windows updates, such as critical, security, driver, service packs, and so on, please see the followingImprovements and fixes
This security update includes quality improvements. Key changes include the following:
-
Adds Advanced Encryption Standard (AES) encryption protections for CVE-2021-33757. For more information, see KB5004605.
-
Removes support for the PerformTicketSignature setting and permanently enables Enforcement mode. For more information and additional steps to enable protection on domain controller servers, see Managing deployment of Kerberos S4U changes for CVE-2020-17049.
-
Security updates to Windows Apps, Windows Fundamentals, Windows Authentication, Windows Operating System Security, and Windows Graphics.
For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.
Known issues in this update
Symptom |
Workaround |
After installing updates released July 13, 2021 on domain controllers (DCs) in your environment, printers, scanners, and multifunction devices which are not compliant with section 3.2.1 of RFC 4556 spec, might fail to print when using smart-card (PIV) authentication. |
For more information on this issue, please see KB5005408 - Smart-card authentication might cause print and scan failures. |
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.
If you use Windows Update, the latest SSU (KB5001403) will be offered to you automatically. To get the standalone package for the latest SSU, search for it in the Microsoft Update Catalog.
REMINDER If you are using Security-only updates, you will also need to install all previous Security-only updates and the latest cumulative update for Internet Explorer (KB5004233).
Install this update
Release Channel |
Available |
Next Step |
Windows Update and Microsoft Update |
No |
See the other options below. |
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 8.1, Windows Server 2012 R2, Windows Embedded 8.1 Industry Enterprise, Windows Embedded 8.1 Industry Pro Classification: Security Update |
File information
For a list of the files that are provided in this update, download the file information for update 5004285.