Microsoft · Security update · July 13, 2021

KB5004245: July 2021 cumulative update for Windows 10 1909

KB5004245, released July 13, 2021, fixes 66 CVEs across 4 products. 3 of them are being exploited (CVE-2021-34448); 3 on CISA KEV. Patch Radar priority: Patch now. The product is no longer supported.

Patch now3 on CISA KEV2 publicly disclosedUnsupported product

CVEs closed

4 rated Critical

Exploited

CVE-2021-34448

Exploitation more likely

Microsoft's assessment

Highest EPSS

0.4006

98th percentile

Priority of the 66 CVEs

Patch now 3
                                Urgent 4
                                High 39
                                Routine 20

Applies to

Product	Build after install
Windows 10 Version 1909 for 32-bit Systems	18363.1679
Windows 10 Version 1909 for ARM64-based Systems	18363.1679
Windows 10 Version 1909 for x64-based Systems	18363.1679
Windows Server, version 1909 (Server Core installation)	18363.1679

CVEs this fix closes

Priority	CVE	Component	Impact	CVSS	EPSS	Exploitation
Patch now	CVE-2021-34448	Microsoft Scripting Engine	Remote Code Execution	6.8	0.4006	KEVExploited
Patch now	CVE-2021-33771	Windows Kernel	Elevation of Privilege	7.8	0.1017	KEVExploited
Patch now	CVE-2021-31979	Windows Kernel	Elevation of Privilege	7.8	0.0454	KEVExploited
Urgent	CVE-2021-34449	Windows Win32K	Elevation of Privilege	7.0	0.0271	More likely
Urgent	CVE-2021-34450	Role: Windows Hyper-V	Remote Code Execution	8.5	0.0250	Exploitation Less Likely
Urgent	CVE-2021-34503	Microsoft Windows Media Foundation	Remote Code Execution	7.8	0.0231	Exploitation Less Likely
Urgent	CVE-2021-34497	Windows MSHTML Platform	Remote Code Execution	6.8	0.0215	Exploitation Less Likely
High	CVE-2021-31183	Windows TCP/IP	Denial of Service	7.5	0.0384	Exploitation Less Likely
High	CVE-2021-34504	Windows Address Book	Remote Code Execution	7.8	0.0347	Exploitation Less Likely
High	CVE-2021-33788	Windows Local Security Authority Subsystem Service (LSASS)	Denial of Service	7.5	0.0328	Exploitation Less Likely
High	CVE-2021-34476	Common Internet File System	Denial of Service	7.5	0.0328	Exploitation Less Likely
High	CVE-2021-34490	Windows TCP/IP	Denial of Service	7.5	0.0328	Exploitation Less Likely
High	CVE-2021-33785	Windows AF_UNIX Socket Provider	Denial of Service	7.5	0.0325	Exploitation Less Likely
High	CVE-2021-34489	Microsoft Graphics Component	Remote Code Execution	7.8	0.0247	Exploitation Less Likely
High	CVE-2021-34492	Windows PFX Encryption	Spoofing	8.1	0.0247	DisclosedExploitation Less Likely
High	CVE-2021-33749	Role: DNS Server	Remote Code Execution	8.8	0.0242	Exploitation Less Likely
High	CVE-2021-33750	Role: DNS Server	Remote Code Execution	8.8	0.0242	Exploitation Less Likely
High	CVE-2021-33752	Role: DNS Server	Remote Code Execution	8.8	0.0242	Exploitation Less Likely
High	CVE-2021-33781	Windows Active Directory	Security Feature Bypass	8.1	0.0241	DisclosedExploitation Less Likely
High	CVE-2021-33756	Role: DNS Server	Remote Code Execution	8.8	0.0241	Exploitation Less Likely
High	CVE-2021-34521	Microsoft Windows Codecs Library	Remote Code Execution	7.8	0.0238	Exploitation Less Likely
High	CVE-2021-34508	Windows Kernel	Remote Code Execution	8.8	0.0225	Exploitation Less Likely
High	CVE-2021-34438	Microsoft Graphics Component	Remote Code Execution	7.8	0.0222	Exploitation Less Likely
High	CVE-2021-34441	Microsoft Windows Media Foundation	Remote Code Execution	7.8	0.0222	Exploitation Less Likely
High	CVE-2021-34446	Windows HTML Platform	Security Feature Bypass	8.0	0.0205	Exploitation Less Likely

Released the same day

KB5001949
Microsoft Word 2016 (32-bit edition), Microsoft Word 2016 (64-bit edition)
KB5001973
Microsoft Office Online Server
KB5001975
Microsoft SharePoint Server 2019
KB5001976
Microsoft SharePoint Enterprise Server 2016
KB5001977
Microsoft Excel 2016 (32-bit edition), Microsoft Excel 2016 (64-bit edition)
KB5001979
Microsoft Office 2016 (32-bit edition), Microsoft Office 2016 (64-bit edition)
KB5001981
Microsoft SharePoint Enterprise Server 2016
KB5001983
Microsoft Office 2013 RT Service Pack 1, Microsoft Office 2013 Service Pack 1 (32-bit editions), Microsoft Office 2013 Service Pack 1 (64-bit editions)
KB5001984
Microsoft SharePoint Enterprise Server 2013 Service Pack 1
KB5001986
Microsoft Office Web Apps Server 2013 Service Pack 1
KB5001992
Microsoft SharePoint Foundation 2013 Service Pack 1
KB5001993
Microsoft Excel 2013 RT Service Pack 1, Microsoft Excel 2013 Service Pack 1 (32-bit editions), Microsoft Excel 2013 Service Pack 1 (64-bit editions)

Vendor advisory

https://support.microsoft.com/help/5004245

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