Microsoft · Security update · February 10, 2026

KB5075904: February 2026 cumulative update for Windows 10 1809

KB5075904, released February 10, 2026, fixes 24 CVEs across 4 products. 5 of them are being exploited (CVE-2026-21510); 5 on CISA KEV. Patch Radar priority: Patch now.

Patch now5 on CISA KEV2 publicly disclosed

CVEs closed

None rated Critical

Exploited

CVE-2026-21510

Exploitation more likely

Microsoft's assessment

Highest EPSS

0.6124

99th percentile

Priority of the 24 CVEs

Patch now 5
                                Urgent 3
                                High 14
                                Routine 2

Applies to

Product	Build after install
Windows 10 Version 1809 for 32-bit Systems	17763.8389
Windows 10 Version 1809 for x64-based Systems	17763.8389
Windows Server 2019	17763.8389
Windows Server 2019 (Server Core installation)	17763.8389

CVEs this fix closes

Priority	CVE	Component	Impact	CVSS	EPSS	Exploitation
Patch now	CVE-2026-21510	Windows Shell	Security Feature Bypass	8.8	0.6124	KEVDisclosedExploited
Patch now	CVE-2026-21513	MSHTML Framework	Security Feature Bypass	8.8	0.1585	KEVDisclosedExploited
Patch now	CVE-2026-21525	Windows Remote Access Connection Manager	Denial of Service	6.2	0.0504	KEVExploited
Patch now	CVE-2026-21533	Windows Remote Desktop	Elevation of Privilege	7.8	0.0434	KEVExploited
Patch now	CVE-2026-21519	Desktop Window Manager	Elevation of Privilege	7.8	0.0257	KEVExploited
Urgent	CVE-2026-21238	Windows Ancillary Function Driver for WinSock	Elevation of Privilege	7.8	0.0333	More likely
Urgent	CVE-2026-21231	Windows Kernel	Elevation of Privilege	7.8	0.0252	More likely
Urgent	CVE-2026-21253	Mailslot File System	Elevation of Privilege	7.0	0.0079	More likely
High	CVE-2026-20846	Windows GDI+	Denial of Service	7.5	0.0141	Exploitation Less Likely
High	CVE-2026-21243	Windows LDAP - Lightweight Directory Access Protocol	Denial of Service	7.5	0.0141	Exploitation Unlikely
High	CVE-2026-21244	Role: Windows Hyper-V	Remote Code Execution	7.3	0.0131	Exploitation Less Likely
High	CVE-2026-21248	Role: Windows Hyper-V	Remote Code Execution	7.3	0.0131	Exploitation Less Likely
High	CVE-2026-21235	Microsoft Graphics Component	Elevation of Privilege	7.3	0.0073	Exploitation Less Likely
High	CVE-2026-21247	Role: Windows Hyper-V	Remote Code Execution	7.3	0.0058	Exploitation Less Likely
High	CVE-2026-21508	Windows Storage	Elevation of Privilege	7.0	0.0044	Exploitation Less Likely
High	CVE-2026-21236	Windows Ancillary Function Driver for WinSock	Elevation of Privilege	7.8	0.0044	Exploitation Unlikely
High	CVE-2026-21239	Windows Kernel	Elevation of Privilege	7.8	0.0044	Exploitation Less Likely
High	CVE-2026-21246	Microsoft Graphics Component	Elevation of Privilege	7.8	0.0044	Exploitation Unlikely
High	CVE-2026-21251	Windows Cluster Client Failover	Elevation of Privilege	7.8	0.0044	Exploitation Unlikely
High	CVE-2026-21255	Role: Windows Hyper-V	Security Feature Bypass	8.8	0.0038	Exploitation Less Likely
High	CVE-2026-21240	Windows HTTP.sys	Elevation of Privilege	7.8	0.0028	Exploitation Less Likely
High	CVE-2026-21234	Windows Connected Devices Platform Service	Elevation of Privilege	7.0	0.0027	Exploitation Unlikely
Routine	CVE-2026-21249	Windows NTLM	Spoofing	3.3	0.1128	Exploitation Less Likely
Routine	CVE-2026-21222	Windows Kernel	Information Disclosure	5.5	0.0060	Exploitation Less Likely

Released the same day

KB5002833
Microsoft SharePoint Server Subscription Edition
KB5002834
Microsoft SharePoint Server 2019
KB5002835
Office Online Server
KB5002836
Microsoft SharePoint Server 2019
KB5002837
Microsoft Excel 2016 (32-bit edition), Microsoft Excel 2016 (64-bit edition)
KB5002839
Microsoft Outlook 2016 (32-bit edition), Microsoft Outlook 2016 (64-bit edition), Microsoft Word 2016 (32-bit edition) and 1 more
KB5002840
Microsoft SharePoint Enterprise Server 2016
KB5002841
Microsoft SharePoint Enterprise Server 2016
KB5074992
Microsoft Exchange Server Subscription Edition RTM
KB5074993
Microsoft Exchange Server 2019 Cumulative Update 15
KB5074994
Microsoft Exchange Server 2019 Cumulative Update 14
KB5074995
Microsoft Exchange Server 2016 Cumulative Update 23

Vendor advisory

https://support.microsoft.com/help/5075904

Our write-up

February 2026 Patch Tuesday: Six Actively Exploited Zero-Days Make This an Emergency

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