Microsoft has published the December 2020 security updates.

The December security release consists of security updates for the following software:

• Microsoft Windows
• Microsoft Edge (EdgeHTML-based)
• Microsoft Edge for Android
• ChakraCore
• Microsoft Office and Microsoft Office Services and Web Apps
• Microsoft Exchange Server
• Azure DevOps
• Microsoft Dynamics
• Visual Studio
• Azure SDK
• Azure Sphere

Please note the following information regarding the security updates:

• See our blog detailing the benefits of the new Security Update Guide layout  here.
• Microsoft is improving Windows Release Notes. For more information, please see  What's next for Windows release notes.
• For information regarding enabling Windows 10, version 2004 features, please see Windows 10, version 20H2 delivery options. Note that Windows 10, versions 2004 and 20H2 share a common core operating system with an identical set of system files. They will also share the same security update KBs.
• For information regarding enabling Windows 10, version 1909 features, please see Windows 10, version 1909 delivery options. Note that Windows 10, versions 1903 and 1909 share a common core operating system with an identical set of system files. They will also share the same security update KBs.
• 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.
• 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.
• Updates for Windows RT 8.1 and Microsoft Office RT software are only available via  Windows 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.

The following CVEs have FAQs with additional information and may include * further steps to take after installing the updates. Please note that this is not a complete list of CVEs for this release.

• CVE-2020-16996
• CVE-2020-17094
• CVE-2020-17095
• CVE-2020-17096
• CVE-2020-17098
• CVE-2020-17099
• CVE-2020-17115
• CVE-2020-17119
• CVE-2020-17120
• CVE-2020-17121
• CVE-2020-17122
• CVE-2020-17123
• CVE-2020-17124
• CVE-2020-17125
• CVE-2020-17126
• CVE-2020-17127
• CVE-2020-17128
• CVE-2020-17129
• CVE-2020-17130
• CVE-2020-17132
• CVE-2020-17133
• CVE-2020-17138
• CVE-2020-17140
• CVE-2020-17141
• CVE-2020-17142
• CVE-2020-17143
• CVE-2020-17144
• CVE-2020-17147
• CVE-2020-17148
• CVE-2020-17152
• CVE-2020-17153
• CVE-2020-17156
• CVE-2020-17158
• CVE-2020-17160

Known Issues

The following KBs contain information about known issues with the security updates. For a complete list of security update KBs, please see  20201208. 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
4592438	Windows 10, version 2004, Windows Server version 2004, Windows 10, version 20H2, Windows Server version 20H2
4592440	Windows 10 Version 1809, Windows Server 2019
4592449	Windows 10, version 1903, Windows Server version 1903, Windows 10, version 1909, Windows Server version 1909
4592468	Windows Server 2012 (Monthly Rollup)
4592471	Windows 7, Windows Server 2008 R2 (Monthly Rollup)
4592484	Windows 8.1, Windows Server 2012 R2 (Monthly Rollup)
4592495	Windows 8.1, Windows Server 2012 R2 (Security-only update)
4592497	Windows Server 2012 (Security-only update)
4592498	Windows Server 2008 (Monthly Rollup)
4592503	Windows 7, Windows Server 2008 R2 (Security-only update)
4592504	Windows Server 2008 (Security-only update)
4593226	Windows 10, version 1607, Windows Server 2016
4593465	Exchange Server 2019, Exchange Server 2016
4593466	Exchange Server 2013
4593467	Exchange Server 2010 Service Pack 3

Security Update Guide - Microsoft Security Response Center