- May 2021 Security Updates release notes
- List of software updates for Microsoft products
- List of the latest Windows Updates and Services Packs
- Security Updates Guide
- Microsoft Update Catalog site
- Our in-depth Windows update guide
- How to install optional updates on Windows 10
- Windows 10 Update History
- Windows 8.1 Update History
- Windows 7 Update History
Microsoft Windows Security Updates May 2021 overview
It is the second Tuesday of the month, and that means it is Patch Day at Microsoft. Microsoft released security and non-security updates for all supported versions of the company's Windows operating system and other company products today.
Our overview is designed for home administrators and system administrators who install security patches on devices running Windows. It links to all support pages, direct downloads of the major Windows patches, includes links to critical issues and known issues.
You can check out the April 2021 Patch Day overview here.
The Microsoft Windows Security Updates: May 2021
You may download the following Excel spreadsheet to get a list of the security updates released for Microsoft Windows and other company products: windows-security-updates-may-2021
Executive Summary
- Non-Enterprise editions of Windows 10 version 1909 reach end of servicing today (Home, Pro, Pro Education and Pro Workstation). Microsoft lifted the last upgrade safeguards of Windows 10 version 2004 and 20H2 recently.
- Microsoft released security updates for all supported versions of Windows (client and server).
- All Windows client products are affected by known issues.
- Other Microsoft products with security updates are: Microsoft Office, Internet Explorer, Visual Studio, Skype for Business, .NET Core.
Operating System Distribution
- Windows 7 (extended support only): 11 vulnerabilities: 2 critical and 9 important
- Hyper-V Remote Code Execution Vulnerability - CVE-2021-28476
- OLE Automation Remote Code Execution Vulnerability -- CVE-2021-31194
- Windows 8.1: 12 vulnerabilities: 2 critical and 12 important
- Hyper-V Remote Code Execution Vulnerability - CVE-2021-28476
- OLE Automation Remote Code Execution Vulnerability -- CVE-2021-31194
- Windows 10 version 1903 and 1909: 16 vulnerabilities: 2 critical and 14 important
- same as Windows 8.1
- Windows 10 version 2004 and 20H2: 24 vulnerabilities, 3 critical and 21 important
- Hyper-V Remote Code Execution Vulnerability - CVE-2021-28476
- OLE Automation Remote Code Execution Vulnerability -- CVE-2021-31194
- HTTP Protocol Stack Remote Code Execution Vulnerability -- CVE-2021-31166
Windows Server products
- Windows Server 2008 R2 (extended support only): 10 vulnerabilities: 1 critical and 9 important
- Hyper-V Remote Code Execution Vulnerability -- CVE-2021-28476
- Windows Server 2012 R2: 12 vulnerabilities: 2 critical and 12 important
- Hyper-V Remote Code Execution Vulnerability - CVE-2021-28476
- OLE Automation Remote Code Execution Vulnerability -- CVE-2021-31194
- Windows Server 2016: 12 vulnerabilities: 2 critical and 12 important.
- same as Windows Server 2021 R2
- Windows Server 2019: 16 vulnerabilities: 2 critical and 14 important
- same as Windows Sever 2008 R2
Windows Security Updates
Windows 7 SP1 and Windows Server 2008 R2
Updates and improvements:
- Fixed an issue in the Server Message Block (SMB) protocol causing frequent crashes with error 0xA on Windows Server 2008 R2 SP1
- Security updates
Windows 8.1 and Windows Server 2012 R2
Updates and improvements:
- Security updates
Windows 10 version 1909
- Support Page: KB5003169
Updates and improvements:
- Fixed an issue that could make scroll bar controls appear blank on the screen.
- Security updates.
Windows 10 version 2004 and 20H2
- Support Page: KB5003173
Updates and improvements:
- Security updates
Other security updates
2021-05 Cumulative Security Update for Internet Explorer (KB5003165)
2021-05 Security Only Quality Update for Windows Embedded 8 Standard and Windows Server 2012 (KB5003203)
2021-05 Security Monthly Quality Rollup for Windows Embedded 8 Standard and Windows Server 2012 (KB5003208)
2021-05 Security Monthly Quality Rollup for Windows Server 2008 (KB5003210)
2021-05 Security Only Quality Update for Windows Server 2008 (KB5003225)
2021-05 Cumulative Update for Windows Server 2019 and Windows 10 Version 1809 (KB5003171)
2021-05 Cumulative Update for Windows 10 Version 1803 (KB5003174)
2021-05 Cumulative Update for Windows Server 2016 and Windows 10 Version 1607 (KB5003197)
2021-05 Servicing Stack Update for Windows 10 Version 1803 (KB5003364)
2021-05 Servicing Stack Update for Windows Server 2019 and Windows 10 Version 1809 (KB5003243)
2021-05 Servicing Stack Update for Windows Server, version 1909 and Windows 10 Version 1909 (KB5003244)
Known Issues
Windows 7 SP1 and Windows Server 2008 R2 SP1
- Update installations are reverted if the system is not supported for ESU.
- Certain operations may fail on Cluster Shared Volumes. Workaround available, see support page.
Windows 8.1 and Windows Server 2012 R2
- Certain operations may fail on Cluster Shared Volumes. Workaround available, see support page.
Windows 10 version 1909
- System and certificates may be lost when a device is updated to a newer version of Windows 10. See the workaround on the support page.
Windows 10 version 2004 and 20H2
- Microsoft Edge Legacy may have been removed on devices with Windows installations created from custom offline media or ISO images, but the browser may not have been replaced by the new Edge. Workaround is available, see support page.
- Performance issues in games after update installation. Is resolved for consumer and non-managed business devices.
- Kanji characters entered using the Microsoft Japanese Input Method Editor may result in incorrect characters being displayed.
Security advisories and updates
ADV 990001Â -- Latest Servicing Stack Updates
Non-security related updates
2021-05 Security and Quality Rollup for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB5001843)
2021-05 Security and Quality Rollup for .NET Framework 4.8 for Windows Embedded 8 Standard and Windows Server 2012 (KB5001844)
2021-05 Security and Quality Rollup for .NET Framework 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB5001845)
2021-05 Security and Quality Rollup for .NET Framework 4.6 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB5001848)
2021-05 Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded 8 Standard and Windows Server 2012 (KB5001849)
2021-05 Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows 8.1 and Windows Server 2012 R2 (KB5001850)
2021-05 Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB5001878)
2021-05 Security and Quality Rollup for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded 8 Standard and Windows Server 2012 (KB5001880)
2021-05 Security and Quality Rollup for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB5001881)
2021-05 Security and Quality Rollup for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB5001882)
2021-05 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows Server, version 2004, and Windows 10 Version 2004 (KB4601554)
2021-05 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows Server, version 1909 and Windows 10 Version 1909 (KB4601556)
2021-05 Cumulative Update for .NET Framework 4.8 for Windows Server 2016 and Windows 10 Version 1607 (KB5001841)
2021-05 Cumulative Update for .NET Framework 4.8 for Windows 10 Version 1803 and Windows Server 2016 (1803) for x64 (KB5001842)
2021-05 Cumulative Update for .NET Framework 3.5, 4.7.2 and 4.8 for Windows Server 2019 and Windows 10 Version 1809 (KB5001879)
2021-05 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 Version 20H2, Windows 10 Version 2004, Windows 10 Version 1909, and Windows 10 Version 1903 (KB5003266)
Windows Malicious Software Removal Tool (KB890830)
Microsoft Office Updates
You find Office update information here.
How to download and install the May 2021 security updates
Updates for home Windows systems are usually installed automatically through Windows Updates. Windows checks for updates regularly and will install security updates automatically, if discovered during checks.
Administrators may run manual checks for updates to speed up the discovery and thus installation of today's security updates.
Note: we recommend that you make backups of important date, best the entire system, before installing any updates.
Windows administrators may run the following steps to check for updates manually on Windows devices:
- Select Start, type Windows Update and load the Windows Update item that is displayed.
- Select check for updates to run a manual check for updates.
Direct update downloads
Below are resource pages with direct download links, if you prefer to download the updates to install them manually.
Windows 7 and Server 2008 R2
- KB5003233 -- 2021-05 Security Monthly Quality Rollup for Windows 7
- KB5003228 -- 2021-05 Security Only Quality Update for Windows 7
Windows 8.1 and Windows Server 2012 R2
- KB5003209 -- 2021-05 Security Monthly Quality Rollup for Windows 8.1
- KB5003220 -- 2021-05 Security Only Quality Update for Windows 8.1
Windows 10 (version 1909)
- KB5003171 -- 2021-05 Cumulative Update for Windows 10 Version 1909
Windows 10 (version 2004)
- KB5003173 -- 2021-05 Cumulative Update for Windows 10 Version 2004
Windows 10 (version 20H2)
- KB5003173 -- 2021-05 Cumulative Update for Windows 10 Version 20H2
Additional resources
Summary
Article Name
Microsoft Windows Security Updates May 2021 overview
Description
Microsoft released security and non-security updates for all supported versions of the company's Windows operating system and other company products today.
Author
Martin Brinkmann
Publisher
Ghacks Technology News
Logo
What mental age of reader are you targeting with the first sentence? 10?
Why not write an article on how to *avoid* upgrading from W10 to W11. Analogous to those like me who avoided upgrading from 7 to 10 for as long as possible.
If your paymaster Microsoft permits it, of course.
5. Rufus
6. Ventoy
PS. I hate reading these “SEO optimized” articles.
I used Rufus to create an installer for a 6th gen intel i5 that had MBR. It upgraded using Setup. No issues except for Win 11 always prompting me to replace my local account. Still using Win 10 Pro on all my other PCs to avoid the bullying.
bit pointless to upgrade for the sake of upgrading as you never know when you’ll get locked out because ms might suddenly not provide updates to unsupported systems.
ps…. time travelling?
written. Jan 15, 2023
Updated • Jan 13, 2023
This happens when you schedule a post in WordPress and update it before setting the publication date.
Anyone willing to downgrade to this awful OS must like inflicting themselves with harm.
I have become convinced now that anybody who has no qualms with using Windows 11/10 must fit into one of the following brackets:
1) Too young to remember a time before W10 and W11 (doesn’t know better)
2) Wants to play the latest games on their PC above anything else (or deeply needs some software which already dropped W7 support)
3) Doesn’t know too much about how computers work, worried that they’d be absolutely lost and in trouble without the “”latest security””
4) Microsoft apologist that tries to justify that the latest “features” and “changes” are actually a good thing, that improve Windows
5) Uses their computer to do a bare minimum of like 3 different things, browse web, check emails, etc, so really doesn’t fuss
Obviously that doesn’t cover everyone, there’s also the category that:
6) Actually liked W7 more than 10, and held out as long as possible before switching, begrudgingly uses 10 now
Have I missed any group off this list?
You have missed in this group just about any professional user that uses business software like CAD programs or ERP Programs which are 99% of all professional users from this list.
Linux doesn’t help anyone who is not a linux kid and apple is just a fancy facebook machine.
Microsoft has removed KB5029351 update
only from windows update though
KB5029351 is still available from the ms update catalog site
1. This update is labaled as PREVIEW if it causes issues to unintelligent people, then they shouldn’t have allowed Preview updates ot install.
2. I have installed it in a 11 years old computer, and no problems at all.
3. Making a big drama over a bluescreen for an updated labeled as preview is ridiculous.
This is probably another BS internet drama where people ran programs and scripts that modified the registry until they broke Windows, just for removing stuff that they weren’t even using just for the sake of it.
Maybe people should stop playing geeks and actually either use Windows 10 or Windows 11, but don’t try to modify things just for the sake of it.
Sometimes removing or stopping things (like defender is a perfect example) only need intelligence, not scripts or 3rd party programs that might mess with windows.
Windows 11 was a pointless release, it was just created because some of the Windows team wanted to boost sales with some sort of new and improved Windows 10. Instead, Microsoft cannot support one version well let alone two.
Windows 11 is the worst ugly shame by Microsoft ever. They should release with every new W11 version a complete free version of Starallback inside just to make this sh** OS functionally again.
motherboard maker MSI has recently released a statement regarding the “unsupported processor” blue screen error for their boards using Intel 600/700 series chipsets & to avoid the KB5029351 Win11 update:
https://www.msi.com/news/detail/MSI-On–UNSUPPORTED-PROCESSOR–Error-Message-of-Windows-11-Update-KB5029351-Preview-142215
check out the following recent articles:
Neowin – Microsoft puts little blame on its Windows update after UNSUPPORTED PROCESSOR BSOD bug:
https://www.neowin.net/news/microsoft-puts-little-blame-on-its-windows-update-after-unsupported-processor-bsod-bug/
BleepingComputer – Microsoft blames ‘unsupported processor’ blue screens on OEM vendors:
https://www.bleepingcomputer.com/news/microsoft/microsoft-blames-unsupported-processor-blue-screens-on-oem-vendors/
While there may be changes or updates to the Windows 10 Store for Business and Education in the future, it is premature to conclude that it will be discontinued based solely on rumors.
My advice, I left win 15 years ago. Now I’m a happy linux user (linuxmint) but there is Centos, Fedora, Ubuntu depending on your needs.
motherboard maker MSI has recently released new BIOS/firmware updates for their Intel 600 & 700 series motherboards to fix the “UNSUPPORTED_PROCESSOR” problem (Sept. 6):
https://www.msi.com/news/detail/Updated-BIOS-fixes-Error-Message–UNSUPPORTED-PROCESSOR–caused-BSOD-on-MSI-s-Intel-700-and-600-Series-Motherboards-142277
I try to disable the Diagnostics Tracking Service (Connected Devices Platform User Services) but it wont let me disable it, any help will be greatly appreciated.
Tank you for your help