KB5124012BMonthly security release (Patch Tuesday) · 2026-09 B

Monthly security release (Patch Tuesday) for Windows 11, version 26H1

Support article Update Catalog CVEs in Security CVE list for a ticket

Is it safe to deploy?

SupersededKB5124012B

Deploy KB5129194 instead; it includes these fixes.

UrgencyCritical · 1 exploited RiskModerate · 2 mitigated

Everything in the September 2026 Patch Tuesday cycle

1Windows version

627CVEs fixed · 53 critical

1Exploited or in CISA KEV

2Open known issues affecting it

YesRestart required (per MSRC)

Applies to

From Microsoft's release-information tables

Servicing branch	OS build	Release	Available
Windows 11, version 26H1	28000.2954	B 2026-09 B	8 Sep 2026

Known issues in this update

Windows release health

Mitigatedfrom KB5124012Win 11 26H1updated 16 Sep

Domain-joined devices might lose their secure trust relationship with the domainSome Credential Guard protected machine accounts might be unable to sign in interactively will valid domain credentials.
Mitigatedfrom KB5124012Win 11 26H1updated 14 Sep

USB audio devices might fail to start or produce no soundSome USB Audio Class 1.0 devices display Code 10 or fail in multichannel audio modes after installing KB5124008.
Resolvedfrom KB5124012 fixed by KB5129194Win 11 26H1updated 17 Sep

Remote Desktop Services might stop responding after Sept. 2026 security updateSome Windows devices with Remote Desktop enabled might experience Remote Desktop Services (RDS) instability.
Resolvedfrom KB5124012 fixed by KB5129194Win 11 26H1updated 14 Sep

Host folder shares might be unavailable in Hyper-V-based Linux VMsPlan9 host folder shares might not appear in the guest environment after installing the September 2026 security update.

Issues this update resolves

Resolvedfrom KB5121000 fixed by KB5124012Win 11 26H1, Win 11 25H2, Win 11 24H2updated 8 Sep

Microsoft Teams and Outlook might fail to launch on ARM-based devicesThis most likely occurs on new PCs after installing the August Windows security update and does not affect other apps.

Security fixes

627 Microsoft CVEs · most urgent first

CVE	Vulnerability	Severity	CVSS	EPSS	Impact	Status
CVE-2026-81963	Windows Update Stack Elevation of Privilege VulnerabilityWindows Update Stack	Important	7.8	0.4%	Elevation of Privilege	ExploitedCISA KEV · due 22 SepRevised 15 Sep
CVE-2026-69579	Windows Message Queuing Remote Code Execution VulnerabilityWindows Message Queuing	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-69590	Windows Routing and Remote Access Service (RRAS) Remote Code Execution VulnerabilityWindows Routing and Remote Access Service (RRAS)	Critical	9.8	1.0%	Remote Code Execution	Revised 24 Sep
CVE-2026-69769	Windows HTTP Print Provider Remote Code Execution VulnerabilityWindows HTTP Print Provider	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-69829	Windows Shell Remote Code Execution VulnerabilityWindows Shell	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-70296	Windows Imaging Component Remote Code Execution VulnerabilityWindows Imaging Component	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-72982	Windows Netlogon Remote Code Execution VulnerabilityWindows Netlogon	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-72983	Internet Connection Sharing (ICS) Remote Code Execution VulnerabilityWindows Internet Connection Sharing (ICS)	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-73009	Windows Secure Socket Tunneling Protocol (SSTP) Remote Code Execution VulnerabilityWindows Secure Socket Tunneling Protocol (SSTP)	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-77493	Windows Graphics Component Remote Code Execution VulnerabilityMicrosoft Graphics Component	Critical	9.8	1.0%	Remote Code Execution
CVE-2026-69499	Windows Imaging Component Remote Code Execution VulnerabilityWindows Imaging Component	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-69518	Windows Remote Desktop Remote Code Execution VulnerabilityWindows Remote Desktop	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-69601	Microsoft Windows Media Foundation Remote Code Execution VulnerabilityMicrosoft Windows Media Foundation	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-69676	Windows Kerberos Remote Code Execution VulnerabilityWindows Kerberos	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-69740	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	8.8	0.3%	Elevation of Privilege
CVE-2026-69784	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	8.8	0.3%	Elevation of Privilege
CVE-2026-69860	Windows Imaging Component Remote Code Execution VulnerabilityWindows Imaging Component	Critical	8.8	0.8%	Remote Code Execution	Revised 11 Sep
CVE-2026-70203	Windows Media Player Remote Code Execution VulnerabilityWindows Media Player	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-70586	Windows Paint Remote Code Execution VulnerabilityWindows Paint	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-72950	Windows Routing and Remote Access Service (RRAS) Remote Code Execution VulnerabilityWindows Routing and Remote Access Service (RRAS)	Critical	8.8	0.9%	Remote Code Execution
CVE-2026-72959	Windows Routing and Remote Access Service (RRAS) Remote Code Execution VulnerabilityWindows Routing and Remote Access Service (RRAS)	Critical	8.8	0.9%	Remote Code Execution
CVE-2026-72960	Windows Media Player Remote Code Execution VulnerabilityWindows Media Player	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-72986	Graphic Fonts Remote Code Execution VulnerabilityGraphic Fonts	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-73006	DirectWrite Remote Code Execution VulnerabilityMicrosoft Graphics Component	Critical	8.8	0.8%	Remote Code Execution	Revised 15 Sep
CVE-2026-73013	Windows Imaging Component Remote Code Execution VulnerabilityWindows Imaging Component	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-73018	Graphic Fonts Remote Code Execution VulnerabilityGraphic Fonts	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-73023	Windows Imaging Component Remote Code Execution VulnerabilityWindows Imaging Component	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-77495	Windows Imaging Component Remote Code Execution VulnerabilityWindows Imaging Component	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-77504	Microsoft Office Word Remote Code Execution VulnerabilityMicrosoft Office Word	Critical	8.8	0.8%	Remote Code Execution
CVE-2026-80083	Windows Hyper-V Remote Code Execution VulnerabilityWindows Hyper-V	Critical	8.8	0.3%	Remote Code Execution
CVE-2026-81955	Windows Graphics Component Remote Code Execution VulnerabilityMicrosoft Graphics Component	Critical	8.8	0.8%	Remote Code Execution	Revised 17 Sep
CVE-2026-69820	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-69846	Windows Secure Kernel Mode Elevation of Privilege VulnerabilityWindows Secure Kernel Mode	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-69874	Windows ALPC Elevation of Privilege VulnerabilityWindows ALPC	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-69906	Windows Secure Kernel Mode Elevation of Privilege VulnerabilityWindows Secure Kernel Mode	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-72958	Windows Credential Guard Elevation of Privilege VulnerabilityWindows Credential Guard	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-72961	Windows Hyper-V Elevation of Privilege VulnerabilityWindows Hyper-V	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-72962	Windows USB Video Driver Elevation of Privilege VulnerabilityWindows USB Video Driver	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-81354	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-83939	Windows Secure Kernel Mode Elevation of Privilege VulnerabilityWindows Secure Kernel Mode	Critical	8.2	0.3%	Elevation of Privilege
CVE-2026-72981	IP Helper Remote Code Execution VulnerabilityIP Helper	Critical	8.1	0.7%	Remote Code Execution
CVE-2026-78449	Windows Reliable Multicast Transport Driver (RMCAST) Remote Code Execution VulnerabilityReliable Multicast Transport Driver (RMCAST)	Critical	8.1	0.7%	Remote Code Execution
CVE-2026-69725	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	7.8	0.3%	Elevation of Privilege
CVE-2026-69799	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	7.8	0.2%	Elevation of Privilege
CVE-2026-69864	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	7.8	0.3%	Elevation of Privilege
CVE-2026-83498	Windows Virtualization-Based Security (VBS) Enclave Elevation of Privilege VulnerabilityWindows Virtualization-Based Security (VBS) Enclave	Critical	7.8	0.3%	Elevation of Privilege	Revised 21 Sep
CVE-2026-69710	Windows Hello Elevation of Privilege VulnerabilityWindows Hello	Critical	7.5	0.2%	Elevation of Privilege
CVE-2026-69852	Windows Routing and Remote Access Service (RRAS) Remote Code Execution VulnerabilityWindows Routing and Remote Access Service (RRAS)	Critical	7.5	0.7%	Remote Code Execution
CVE-2026-69890	Windows Virtual Trusted Platform Module Elevation of Privilege VulnerabilityWindows Virtual Trusted Platform Module	Critical	7.5	0.3%	Elevation of Privilege
CVE-2026-73017	Graphics Kernel Remote Code Execution VulnerabilityWindows Graphics Kernel	Critical	7.5	0.3%	Remote Code Execution

Showing 50 of 627All CVEs