Microsoft Releases September 2021 Patch Tuesday Fixes

There are 3 Critical, 62 Important and a single Moderate fix in this September Patch Tuesday. Fixes include Microsoft Windows and Windows components, Microsoft Edge, Azure, Office and Office Components, SharePoint Server, Microsoft Windows DNS, and the Windows Subsystem for Linux.

Year 2 Extended Support – Windows 7 and Windows Server 2008 (including R2) have received some updates this month, with one currently Weaponized.

1. Windows 7 – 2 Critical and 20 Important vulnerabilities fixed
2. Windows 2008 R2 – 2 Critical and 20 Important vulnerabilities fixed

Top September 2021 Patches and Vulnerabilities

Based on the Vendor Severity and CVSS Score, we have made a few recommendations below. As usual, we recommend entering the CVE numbers below into your patch management solution and deploying as soon as possible. 

1. CVE-2021-40444: Microsoft MSHTML Remote Code Execution Vulnerability

The vulnerability exists due to improper input validation within the MSHTML component. A remote attacker can create a specially crafted Office document with a malicious ActiveX control inside, trick the victim into opening the document and execute arbitrary code on the system.

The best course of action is to ensure your staff know what to do when unsolicited emails arrive, and how to escalate to your security teams when such emails are received.

There are several workarounds you can implement here.

Syxscore

• Vendor Severity: Important
• CVSS: 8.8
• Weaponized: Yes
• Public Aware: Yes
• Countermeasure: Yes

Syxscore Risk

• Attack Vector: Network
• Attack Complexity: Low
• Privileges: None
• User Interaction: Required
• Scope (Jump Point): No

 

[dt_divider style=”thin” /]

 

2. CVE-2021-38647: Open Management Infrastructure Remote Code Execution Vulnerability

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system. This vulnerability requires no user interaction or privileges, so an attacker can run their code on an affected system just by sending a specially crafted message to an affected system.

An attacker could send a specially crafted message via HTTPS to port 5986 on a vulnerable system.

Syxscore

• Vendor Severity: Critical
• CVSS: 9.8
• Weaponized: No
• Public Aware: No
• Countermeasure: No 

Syxscore Risk

• Attack Vector: Network
• Attack Complexity: Low
• Privileges: None
• User Interaction: None
• Scope (Jump Point): No

 

[dt_divider style=”thin” /]

 

3. CVE-2021-36954: Windows Bind Filter Driver Elevation of Privilege Vulnerability

The vulnerability allows a local user to escalate privileges on the system. After the privilege escalation, an attacker can then perform other acts of attacks or even affects resources outside of the original attack vector – Solar Winds spring to mind?

Syxscore

• Vendor Severity: Important
• CVSS: 9.8
• Weaponized: No
• Public Aware: No
• Countermeasure: No

Syxscore Risk

• Attack Vector: Local
• Attack Complexity: Low
• Privileges: Low
• User Interaction: None
• Scope (Jump Point): Yes

Syxsense Recommendations

Based on the vendor severity and CVSS Score, we have made a few recommendations below which you should prioritize this month. Please pay close attention to any of these which are publicly aware or weaponized.

 

CVE Reference	Description	Vendor Severity	CVSS Score	Countermeasure	Publicly Aware	Weaponized	Syxsense Recommended
CVE-2021-40444	Microsoft MSHTML Remote Code Execution Vulnerability	Important	8.8	Yes	Yes	Yes	Yes
CVE-2021-38647	Open Management Infrastructure Remote Code Execution Vulnerability	Critical	9.8	No	No	No	Yes
CVE-2021-36954	Windows Bind Filter Driver Elevation of Privilege Vulnerability	Important	8.8	No	No	No	Yes
CVE-2021-36965	Windows WLAN AutoConfig Service Remote Code Execution Vulnerability	Critical	8.8	No	No	No	Yes
CVE-2021-26435	Windows Scripting Engine Memory Corruption Vulnerability	Critical	8.1	No	No	No	Yes
CVE-2021-36967	Windows WLAN AutoConfig Service Elevation of Privilege Vulnerability	Important	8	No	No	No	Yes
CVE-2021-36968	Windows DNS Elevation of Privilege Vulnerability	Important	7.8	No	Yes	No	Yes
CVE-2021-36975	Win32k Elevation of Privilege Vulnerability	Important	7.8	No	No	No	Yes
CVE-2021-38639	Win32k Elevation of Privilege Vulnerability	Important	7.8	No	No	No	Yes
CVE-2021-36963	Windows Common Log File System Driver Elevation of Privilege Vulnerability	Important	7.8	No	No	No	Yes
CVE-2021-36955	Windows Common Log File System Driver Elevation of Privilege Vulnerability	Important	7.8	No	No	No	Yes
CVE-2021-38633	Windows Common Log File System Driver Elevation of Privilege Vulnerability	Important	7.8	No	No	No	Yes
CVE-2021-38671	Windows Print Spooler Elevation of Privilege Vulnerability	Important	7.8	No	No	No	Yes
CVE-2021-38661	HEVC Video Extensions Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38655	Microsoft Excel Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38644	Microsoft MPEG-2 Video Extension Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38646	Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38658	Microsoft Office Graphics Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38660	Microsoft Office Graphics Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38659	Microsoft Office Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38653	Microsoft Office Visio Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38654	Microsoft Office Visio Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38656	Microsoft Word Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38645	Open Management Infrastructure Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38648	Open Management Infrastructure Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-26434	Visual Studio Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-36952	Visual Studio Remote Code Execution Vulnerability	Important	7.8	No	No	No
CVE-2021-38628	Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38638	Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-36964	Windows Event Tracing Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38630	Windows Event Tracing Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38625	Windows Kernel Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38626	Windows Kernel Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38667	Windows Print Spooler Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-40447	Windows Print Spooler Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-36973	Windows Redirected Drive Buffering System Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-36974	Windows SMB Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-36966	Windows Subsystem for Linux Elevation of Privilege Vulnerability	Important	7.8	No	No	No
CVE-2021-38650	Microsoft Office Spoofing Vulnerability	Important	7.6	No	No	No
CVE-2021-38651	Microsoft SharePoint Server Spoofing Vulnerability	Important	7.6	No	No	No
CVE-2021-38652	Microsoft SharePoint Server Spoofing Vulnerability	Important	7.6	No	No	No
CVE-2021-36960	Windows SMB Information Disclosure Vulnerability	Important	7.5	No	No	No
CVE-2021-38634	Microsoft Windows Update Client Elevation of Privilege Vulnerability	Important	7.1	No	No	No
CVE-2021-38649	Open Management Infrastructure Elevation of Privilege Vulnerability	Important	7	No	No	No
CVE-2021-38629	Windows Ancillary Function Driver for WinSock Information Disclosure Vulnerability	Important	6.5	No	No	No
CVE-2021-38624	Windows Key Storage Provider Security Feature Bypass Vulnerability	Important	6.5	No	No	No
CVE-2021-38669	Microsoft Edge (Chromium-based) Tampering Vulnerability	Important	6.4	No	No	No
CVE-2021-40448	Microsoft Accessibility Insights for Android Information Disclosure Vulnerability	Important	6.3	No	No	No
CVE-2021-26436	Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability	Important	6.1	No	No	No
CVE-2021-38641	Microsoft Edge for Android Spoofing Vulnerability	Important	6.1	No	No	No
CVE-2021-38642	Microsoft Edge for iOS Spoofing Vulnerability	Important	6.1	No	No	No
CVE-2021-38657	Microsoft Office Graphics Component Information Disclosure Vulnerability	Important	6.1	No	No	No
CVE-2021-38632	BitLocker Security Feature Bypass Vulnerability	Important	5.7	No	No	No
CVE-2021-26437	Visual Studio Code Spoofing Vulnerability	Important	5.5	No	No	No
CVE-2021-36959	Windows Authenticode Spoofing Vulnerability	Important	5.5	No	No	No
CVE-2021-36961	Windows Installer Denial of Service Vulnerability	Important	5.5	No	No	No
CVE-2021-36962	Windows Installer Information Disclosure Vulnerability	Important	5.5	No	No	No
CVE-2021-36969	Windows Redirected Drive Buffering Sub System Driver Information Disclosure Vulnerability	Important	5.5	No	No	No
CVE-2021-38635	Windows Redirected Drive Buffering Sub System Driver Information Disclosure Vulnerability	Important	5.5	No	No	No
CVE-2021-38636	Windows Redirected Drive Buffering Sub System Driver Information Disclosure Vulnerability	Important	5.5	No	No	No
CVE-2021-36972	Windows SMB Information Disclosure Vulnerability	Important	5.5	No	No	No
CVE-2021-38637	Windows Storage Information Disclosure Vulnerability	Important	5.5	No	No	No
CVE-2021-40440	Microsoft Dynamics Business Central Cross-site Scripting Vulnerability	Important	5.4	No	No	No
CVE-2021-36930	Microsoft Edge (Chromium-based) Elevation of Privilege Vulnerability	Important	5.3	No	No	No
CVE-2021-26439	Microsoft Edge for Android Information Disclosure Vulnerability	Moderate	4.6	No	No	No
CVE-2021-36956	Azure Sphere Information Disclosure Vulnerability	Important	4.4	No	No	No