The Microsoft December 2021 security updates have been released and consist of 67 CVEs. Of these CVEs, 7 are rated Critical, and 60 are rated Important severity. At the time of release, five are listed as publicly known and one is listed as under active exploit.
The updates apply to the following long list of products: Apps, ASP.NET Core & Visual Studio, Azure Bot Framework SDK, BizTalk ESB Toolkit, Internet Storage Name Service, Microsoft Defender for IoT, Microsoft Devices, Microsoft Edge (Chromium-based), Microsoft Local Security Authority Server (lsasrv), Microsoft Message Queuing, Microsoft Office, Microsoft Office Access, Microsoft Office Excel, Microsoft Office SharePoint, Microsoft PowerShell, Microsoft Windows Codecs Library, Office Developer Platform, Remote Desktop Client, Role: Windows Fax Service, Role: Windows Hyper-V, Visual Studio Code, Visual Studio Code - WSL Extension, Windows Common Log File System Driver, Windows Digital TV Tuner, Windows DirectX, Windows Encrypting File System (EFS), Windows Event Tracing, Windows Installer, Windows Kernel, Windows Media, Windows Mobile Device Management, Windows NTFS, Windows Print Spooler Components, Windows Remote Access Connection Manager, Windows Storage, Windows Storage Spaces Controller, Windows SymCrypt, Windows TCP/IP, and Windows Update Stack.
See the KBs listed at
December 2021 Security Updates - Release Notes - Security Update Guide - Microsoft for information regarding known issues with the security updates as well as the CVEs with FAQs, Mitigations and/or Workarounds.
Note: This is the month for the quarterly MSRT run. Although included with Windows updates, it can be downloaded separately:
Recommended Reading: See Dustin Childs review and analysis in
Zero Day Initiative -- The December 2021 Security Update Review.
