Microsoft · Security update · January 9, 2024

KB5034121: January 2024 cumulative update for Windows 11 21H2

KB5034121, released January 9, 2024, fixes 34 CVEs across 2 products. None of them is reported as exploited. Patch Radar priority: Urgent. The product is no longer supported.

UrgentUnsupported product

CVEs closed

2 rated Critical

Exploited

None reported

Exploitation more likely

Microsoft's assessment

Highest EPSS

0.2260

97th percentile

Priority of the 34 CVEs

Patch now 0
                                Urgent 8
                                High 9
                                Routine 17

Applies to

Product	Build after install
Windows 11 version 21H2 for ARM64-based Systems	22000.2713
Windows 11 version 21H2 for x64-based Systems	22000.2713

CVEs this fix closes

Priority	CVE	Component	Impact	CVSS	EPSS	Exploitation
Urgent	CVE-2024-20674	Windows Authentication Methods	Security Feature Bypass	8.8	0.1717	More likely
Urgent	CVE-2024-21310	Windows Cloud Files Mini Filter Driver	Elevation of Privilege	7.8	0.1160	More likely
Urgent	CVE-2024-20698	Windows Kernel	Elevation of Privilege	7.8	0.0865	More likely
Urgent	CVE-2024-20653	Windows Common Log File System Driver	Elevation of Privilege	7.8	0.0449	More likely
Urgent	CVE-2024-20683	Windows Win32K	Elevation of Privilege	7.8	0.0421	More likely
Urgent	CVE-2024-20700	Windows Hyper-V	Remote Code Execution	7.5	0.0395	Exploitation Less Likely
Urgent	CVE-2024-20652	Windows Scripting	Security Feature Bypass	8.1	0.0208	More likely
Urgent	CVE-2024-21307	Remote Desktop Client	Remote Code Execution	7.5	0.0196	More likely
High	CVE-2024-20696	Windows Libarchive	Remote Code Execution	7.3	0.0315	Exploitation Less Likely
High	CVE-2024-20661	Windows Message Queuing	Denial of Service	7.5	0.0276	Exploitation Less Likely
High	CVE-2024-20687	Windows AllJoyn API	Denial of Service	7.5	0.0250	Exploitation Less Likely
High	CVE-2024-20654	Windows ODBC Driver	Remote Code Execution	8.0	0.0199	Exploitation Less Likely
High	CVE-2024-20682	Windows Cryptographic Services	Remote Code Execution	7.8	0.0076	Exploitation Less Likely
High	CVE-2024-21309	Windows Kernel-Mode Drivers	Elevation of Privilege	7.8	0.0076	Exploitation Less Likely
High	CVE-2024-20658	Microsoft Virtual Hard Drive	Elevation of Privilege	7.8	0.0071	Exploitation Less Likely
High	CVE-2024-20681	Windows Subsystem for Linux	Elevation of Privilege	7.8	0.0070	Exploitation Less Likely
High	CVE-2024-20657	Windows Group Policy	Elevation of Privilege	7.0	0.0057	Exploitation Less Likely
Routine	CVE-2024-21320	Windows Themes	Spoofing	6.5	0.2260	Exploitation Less Likely
Routine	CVE-2024-21306	Microsoft Bluetooth Driver	Spoofing	5.7	0.0583	Exploitation Less Likely
Routine	CVE-2024-20666	Windows BitLocker	Security Feature Bypass	6.6	0.0310	Exploitation Less Likely
Routine	CVE-2024-21314	Windows Message Queuing	Information Disclosure	6.5	0.0208	Exploitation Less Likely
Routine	CVE-2024-20660	Windows Message Queuing	Information Disclosure	6.5	0.0204	Exploitation Less Likely
Routine	CVE-2024-20680	Windows Message Queuing	Information Disclosure	6.5	0.0204	Exploitation Less Likely
Routine	CVE-2024-20664	Windows Message Queuing	Information Disclosure	6.5	0.0200	Exploitation Less Likely
Routine	CVE-2024-20663	Windows Message Queuing	Information Disclosure	6.5	0.0193	Exploitation Less Likely

Released the same day

KB5002539
Microsoft SharePoint Server 2019
KB5002540
Microsoft SharePoint Server Subscription Edition
KB5002541
Microsoft SharePoint Enterprise Server 2016
KB5030979
Microsoft Visual Studio 2015 Update 3
KB5033733
.NET 6.0
KB5033734
.NET 7.0
KB5034119
Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1607 for 32-bit Systems, Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1607 for x64-based Systems, Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2016 and 5 more
KB5034120
Windows Server 2008 R2 for x64-based Systems Service Pack 1, Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation), Windows Server 2012 and 3 more
KB5034122
Windows 10 Version 21H2 for 32-bit Systems, Windows 10 Version 21H2 for ARM64-based Systems, Windows 10 Version 21H2 for x64-based Systems and 3 more
KB5034123
Windows 11 Version 22H2 for ARM64-based Systems, Windows 11 Version 22H2 for x64-based Systems, Windows 11 Version 23H2 for ARM64-based Systems and 1 more
KB5034127
Windows 10 Version 1809 for 32-bit Systems, Windows 10 Version 1809 for ARM64-based Systems, Windows 10 Version 1809 for x64-based Systems and 2 more
KB5034129
Windows Server 2022, Windows Server 2022 (Server Core installation)

Vendor advisory

https://support.microsoft.com/help/5034121

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