Microsoft has announced the security updates for October 2021.

October 2021 Security Updates

Updates this Month

This release consists of security updates for the following products, features and roles.

• .NET Core & Visual Studio
• Active Directory Federation Services
• Console Window Host
• HTTP.sys
• Microsoft DWM Core Library
• Microsoft Dynamics
• Microsoft Dynamics 365 Sales
• Microsoft Edge (Chromium-based)
• Microsoft Exchange Server
• Microsoft Graphics Component
• Microsoft Intune
• Microsoft Office Excel
• Microsoft Office SharePoint
• Microsoft Office Visio
• Microsoft Office Word
• Microsoft Windows Codecs Library
• Rich Text Edit Control
• Role: DNS Server
• Role: Windows Active Directory Server
• Role: Windows AD FS Server
• Role: Windows Hyper-V
• System Center
• Visual Studio
• Windows AppContainer
• Windows AppX Deployment Service
• Windows Bind Filter Driver
• Windows Cloud Files Mini Filter Driver
• Windows Common Log File System Driver
• Windows Desktop Bridge
• Windows DirectX
• Windows Event Tracing
• Windows exFAT File System
• Windows Fastfat Driver
• Windows Installer
• Windows Kernel
• Windows MSHTML Platform
• Windows Nearby Sharing
• Windows Network Address Translation (NAT)
• Windows Print Spooler Components
• Windows Remote Procedure Call Runtime
• Windows Storage Spaces Controller
• Windows TCP/IP
• Windows Text Shaping
• Windows Win32K

Please note the following information regarding the security updates:

Security Update Guide Blog Posts

Date	Blog Post
February 9, 2021	Continuing to Listen: Good News about the Security Update Guide API
January 13, 2021	Security Update Guide Supports CVEs Assigned by Industry Partners
December 8, 2020	Security Update Guide: Let’s keep the conversation going
November 9, 2020	Vulnerability Descriptions in the New Version of the Security Update Guide

Relevant Information

• IMPORTANT ANNOUNCEMENT: In the coming months we will be moving to a new, more user-friendly and flexible system for delivering Microsoft Technical Security Notifications. Upcoming information about how you can sign up for and receive these Technical Security Notifications will be coming soon.
• Windows 10 updates are cumulative. The monthly security release includes all security fixes for vulnerabilities that affect Windows 10, in addition to non-security updates. The updates are available via the  Microsoft Update Catalog. For information on lifecycle and support dates for Windows 10 operating systems, please see  Windows Lifecycle Facts Sheet.
• Microsoft is improving Windows Release Notes. For more information, please see  What's next for Windows release notes.
• A list of the latest servicing stack updates for each operating system can be found in  ADV990001. This list will be updated whenever a new servicing stack update is released. It is important to install the latest servicing stack update.
• In addition to security changes for the vulnerabilities, updates include defense-in-depth updates to help improve security-related features.
• Customers running Windows 7, Windows Server 2008 R2, or Windows Server 2008 need to purchase the Extended Security Update to continue receiving security updates. See  4522133 for more information.

FAQs, Mitigations, and Workarounds

The following CVEs have FAQs, Mitigations, or Workarounds. You can see these in more detail from the Vulnerabilities tab by selecting FAQs, Mitigations and Workarounds columns in the Edit Columns panel.

• CVE-2020-1971
• CVE-2021-26427
• CVE-2021-26441
• CVE-2021-3449
• CVE-2021-3450
• CVE-2021-37974
• CVE-2021-37975
• CVE-2021-37976
• CVE-2021-38662
• CVE-2021-38663
• CVE-2021-38672
• CVE-2021-40454
• CVE-2021-40456
• CVE-2021-40457
• CVE-2021-40460
• CVE-2021-40468
• CVE-2021-40469
• CVE-2021-40471
• CVE-2021-40472
• CVE-2021-40473
• CVE-2021-40474
• CVE-2021-40475
• CVE-2021-40479
• CVE-2021-40480
• CVE-2021-40481
• CVE-2021-40482
• CVE-2021-40485
• CVE-2021-40486
• CVE-2021-40487
• CVE-2021-40489
• CVE-2021-41332
• CVE-2021-41336
• CVE-2021-41337
• CVE-2021-41342
• CVE-2021-41343
• CVE-2021-41352
• CVE-2021-41355
• CVE-2021-41361
• CVE-2021-41363

Known Issues

You can see these in more detail from the Deployments tab by selecting Known Issues column in the Edit Columns panel.

For more information about Windows Known Issues, please see  Windows message center (links to currently-supported versions of Windows are in the left pane).

KB Article	Applies To
5006670	Windows 10, Version 20H2
5006672	Windows 10, Version 1809, Windows Server 2019
5006714	Windows 8.1, Windows RT 8.1, Windows Server 2012 R2 (Monthly Rollup)
5006715	Windows Server 2008 SP2 (Security-only update)
5006728	Windows 7, Windows Server 2008 R2 (Security-only update)
5006729	Windows 8.1, Windows RT 8.1, Windows Server 2012 R2 (Security-only update)
5006732	Windows Server 2012 (Security-only update)
5006736	Windows Server 2008 SP2 (Monthly Rollup)
5006739	Windows Server 2012 (Monthly Rollup)
5006743	Windows 7, Windows Server 2008 R2 (Monthly Rollup)
5007011	Exchange Server 2013
5007012	Exchange Server 2016, Exchange Server 2019

Security Update Guide - Microsoft Security Response Center