Microsoft · Security update · April 13, 2021

KB5001393: April 2021 security update

KB5001393, released April 13, 2021, fixes 55 CVEs across 4 products. None of them is reported as exploited. Patch Radar priority: Urgent.

Urgent1 publicly disclosed

CVEs closed

14 rated Critical

Exploited

None reported

Exploitation more likely

Microsoft's assessment

Highest EPSS

0.6410

99th percentile

Priority of the 55 CVEs

Patch now 0
                                Urgent 16
                                High 25
                                Routine 14

Applies to

Product
Windows 8.1 for 32-bit systems
Windows 8.1 for x64-based systems
Windows Server 2012 R2
Windows Server 2012 R2 (Server Core installation)

CVEs this fix closes

Priority	CVE	Component	Impact	CVSS	EPSS	Exploitation
Urgent	CVE-2021-28325	Windows SMB Server	Information Disclosure	6.5	0.6410	More likely
Urgent	CVE-2021-27095	Windows Media Player	Remote Code Execution	7.8	0.0435	Exploitation Less Likely
Urgent	CVE-2021-28333	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0254	Exploitation Less Likely
Urgent	CVE-2021-28329	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28330	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28331	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28332	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28334	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28335	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28336	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28337	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28338	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28339	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28343	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
Urgent	CVE-2021-28315	Windows Media Player	Remote Code Execution	7.8	0.0160	Exploitation Less Likely
Urgent	CVE-2021-27072	Windows Win32K	Elevation of Privilege	7.0	0.0065	More likely
High	CVE-2021-28439	Windows TCP/IP	Denial of Service	7.5	0.0653	Exploitation Less Likely
High	CVE-2021-26415	Windows Installer	Elevation of Privilege	7.8	0.0357	Exploitation Less Likely
High	CVE-2021-28445	Windows Network File System	Remote Code Execution	8.1	0.0290	Exploitation Less Likely
High	CVE-2021-28327	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0254	Exploitation Less Likely
High	CVE-2021-28340	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0254	Exploitation Less Likely
High	CVE-2021-28344	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0254	Exploitation Less Likely
High	CVE-2021-28356	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0254	Exploitation Less Likely
High	CVE-2021-28341	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely
High	CVE-2021-28342	Windows Remote Procedure Call Runtime	Remote Code Execution	8.8	0.0247	Exploitation Less Likely

Released the same day

KB2553491
Microsoft Office 2010 Service Pack 2 (32-bit editions), Microsoft Office 2010 Service Pack 2 (64-bit editions)
KB2589361
Microsoft Office 2010 Service Pack 2 (32-bit editions), Microsoft Office 2010 Service Pack 2 (64-bit editions)
KB3017810
Microsoft Excel 2010 Service Pack 2 (32-bit editions), Microsoft Excel 2010 Service Pack 2 (64-bit editions)
KB3178639
Microsoft Office 2013 Service Pack 1 (32-bit editions), Microsoft Office 2013 Service Pack 1 (64-bit editions)
KB3178643
Microsoft Office 2013 Service Pack 1 (32-bit editions), Microsoft Office 2013 Service Pack 1 (64-bit editions)
KB4493170
Microsoft SharePoint Enterprise Server 2013 Service Pack 1
KB4493185
Microsoft Outlook 2010 Service Pack 2 (32-bit editions), Microsoft Outlook 2010 Service Pack 2 (64-bit editions)
KB4493198
Microsoft Word 2016 (32-bit edition), Microsoft Word 2016 (64-bit edition)
KB4493201
Microsoft SharePoint Enterprise Server 2013 Service Pack 1
KB4493208
Microsoft Word 2013 RT Service Pack 1, Microsoft Word 2013 Service Pack 1 (32-bit editions), Microsoft Word 2013 Service Pack 1 (64-bit editions)
KB4493215
Microsoft Office 2010 Service Pack 2 (32-bit editions), Microsoft Office 2010 Service Pack 2 (64-bit editions)
KB4493218
Microsoft Word 2010 Service Pack 2 (32-bit editions), Microsoft Word 2010 Service Pack 2 (64-bit editions)

Vendor advisory

https://support.microsoft.com/help/5001393

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