Service Notices
Microsoft Releases December 2021 Security Updates
Dec 17, 2021 GMT+08:00
I. Overview
Microsoft has released its December 2021 Security Updates. A total of 67 security vulnerabilities have been disclosed, among which 7 are marked as important vulnerabilities. Attackers can exploit these vulnerabilities to perform remote code execution, escalate privileges, and leak sensitive information. The following software is affected: Microsoft Windows, Microsoft Office, Microsoft Visual Studio Code and Microsoft Defender for IoT.
For details, visit Microsoft official website:
https://msrc.microsoft.com/update-guide/releaseNote/2021-Dec
The following vulnerabilities have been exploited by attackers:
Windows App X Installer Spoofing Vulnerability (CVE-2021-43890): An attacker could craft a malicious attachment to be used in phishing campaigns, then convince the user to open the specially crafted attachment. The POC of this vulnerability has been disclosed. It is a high-risk vulnerability and has been exploited in the wild.
Windows Installer Elevation of Privilege Vulnerability (CVE-2021-43883): Details of the vulnerability have been disclosed.
Windows Mobile Device Management Elevation of Privilege Vulnerability (CVE-2021-43880): Details of the vulnerability have been disclosed.
Windows Print Spooler Elevation of Privilege Vulnerability (CVE-2021-41333): Details of the vulnerability have been disclosed.
Please perform security self-check and security hardening in a timely manner to reduce attack risks.
II. Severity
Severity: important
(Severity: low, moderate, important, and critical)
III. Affected Products
Microsoft Windows, Microsoft Office, Microsoft Visual Studio Code, Microsoft Defender for IoT.
IV. Vulnerability Details
CVE ID | Vulnerability Name | Severity | Affected Product |
CVE-2021-43905 | Microsoft Office app Remote Code Execution Vulnerability | Important | Office app |
CVE-2021-43899 | Microsoft 4K Wireless Display Adapter Remote Code Execution Vulnerability | Important | Microsoft 4K Wireless Display Adapter |
CVE-2021-42310 | Microsoft Defender for IoT Remote Code Execution Vulnerability | Important | Microsoft Defender for IoT |
CVE-2021-43233 | Remote Desktop Client Remote Code Execution Vulnerability | Important | Windows 10, Windows 8.1/RT 8.1, Windows 7, Windows 11, Windows Server 2008R/2012/2012R/2016/2019/2022, Windows Server, version 20H2/2004 |
CVE-2021-43217 | Windows Encrypting File System (EFS) Remote Code Execution Vulnerability | Important | Windows 10, Windows 8.1/RT 8.1, Windows 7, Windows 11, Windows Server 2008/2008R/2012/2012R/2016/2019/2022, Windows Server, version 20H2/2004 |
CVE-2021-43215 | iSNS Server Memory Corruption Vulnerability Can Lead to Remote Code Execution | Important | Windows 10, Windows 8.1/RT 8.1, Windows 7, Windows Server 2008/2008R/2012/2012R/2016/2019, Windows Server, version 20H2/2004 |
CVE-2021-43907 | Visual Studio Code WSL Extension Remote Code Execution Vulnerability | Important | Visual Studio Code WSL Extension |
(Note: Vulnerabilities listed above are important ones. For more information, refer to the official website of Microsoft.)
V. Security Recommendations
1. Use Windows Update or download patches from the following address to fix the vulnerabilities:
https://msrc.microsoft.com/update-guide
2. Back up data remotely to protect your data.
Note: Before fixing vulnerabilities, back up your files and conduct a thorough test.