Summary

This security update resolves vulnerabilities in Adobe Flash Player if it's installed on any supported edition of Windows Server 2016, Windows Server 2012 R2, Windows Server 2012, Windows 10, Windows 10 Version 1511, Windows 10 Version 1607, Windows 8.1, or Windows RT 8.1. To learn more about the vulnerability, see ADV170006.

More Information

Important

  • All future security and nonsecurity updates for Windows Server 2012 R2, Windows 8.1, and Windows RT 8.1 require the installation of update 2919355. We recommend that you install update 2919355 on your Windows Server 2012 R2-based, Windows 8.1-based, or Windows RT 8.1-based computer so that you receive future updates.

  • If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you require before you install this update. For more information, see Add language packs to Windows.

  • This update applies to the Windows operating systems that are listed in the "Applies to" section in this article. If you want to install Adobe Flash Player update on an earlier version of Windows, try Adobe Flash Player download.

Deployment information

For deployment details for this security update, go to the following article in the Microsoft Knowledge Base:

Security update deployment information: May 9, 2017

 

How to obtain and install the update

Method 1: Windows Update

This update is available through Windows Update. When you turn on automatic updating, this update will be downloaded and installed automatically. For more information about how to get security updates automatically, see Windows Update: FAQ. Note For Windows RT 8.1, this update is available through Windows Update only.

Method 2: Microsoft Update Catalog

To get the stand-alone package for this update, go to the Microsoft Update Catalog website.  

Detection and deployment

Security Central You can manage the software and security updates that you have to deploy to the servers, desktops, and mobile systems in your organization. For more information, see the TechNet Update Management Center. TheMicrosoft TechNet Security website provides more information about security in Microsoft products. You can download security updates from the Microsoft Update Catalog. The Microsoft Update Catalog provides a searchable catalog of content that is made available through Windows Update and Microsoft Update. This includes security updates, drivers, and service packs. For more information about the Microsoft Update Catalog, see the Microsoft Update Catalog FAQ.

Detection and deployment guidance Microsoft provides detection and deployment guidance for security updates. This guidance contains recommendations and information that can help IT professionals understand how to use various tools for detection and deployment of security updates. For more information, see Microsoft Knowledge Base article 961747.

Microsoft Baseline Security Analyzer Microsoft Baseline Security Analyzer (MBSA) lets administrators scan local and remote systems for missing security updates and common security misconfigurations. For more information, see Microsoft Baseline Security Analyzer. Note Customers who use legacy software that is not supported by the latest release of MBSA, Microsoft Update, or Windows Server Update Services should see the "Legacy Product Support" section of Microsoft Baseline Security Analyzer. Here, you can find information about how to create comprehensive security update detection by using legacy tools.

Windows Server Update Services Windows Server Update Services (WSUS) lets information technology administrators deploy the latest Microsoft product updates to computers that are running Windows. For more information about how to deploy security updates by using Windows Server Update Services, see the following Microsoft TechNet topic:

Windows Server Update Services

Systems Management Server The following table provides the Microsoft Systems Management Server (SMS) detection and deployment summary for this security update.

Software

SMS 2003 with ITMU

System Center Configuration Manager

Windows 8.1 for 32-bit systems

No

Yes

Windows 8.1 for 64-bit systems

No

Yes

Windows Server 2012 and Windows Server 2012 R2

No

Yes

Note Microsoft discontinued support for SMS 2.0 on April 12, 2011. For SMS 2003, Microsoft also discontinued support for the Security Update Inventory Tool (SUIT) on April 12, 2011. Customers are encouraged to upgrade to System Center Configuration Manager. For SMS 2003, the SMS 2003 Inventory Tool for Microsoft Updates (ITMU) can be used by SMS to detect security updates that are supported by Windows Server Update Services. For more information, see Systems Management Server 2003. System Center Configuration Manager uses WSUS 3.0 to detect updates. For more information, see System Center. For more detailed information, see Microsoft Knowledge Base article 910723: Summary list of monthly detection and deployment guidance articles. Update Compatibility Evaluator and Application Compatibility Toolkit Updates frequently write to the same files and registry settings that are required for your applications to run. This can trigger incompatibilities and increase the time that is required to deploy security updates. You can streamline the testing and validation of Windows updates against installed applications by using the Update Compatibility Evaluator components that are included in the Application Compatibility Toolkit (ACT). The Application Compatibility Toolkit contains the necessary tools and documentation to evaluate and decrease application compatibility issues before you deploy a Windows update, a Microsoft security update, or a new version of Windows Internet Explorer in your environment.

Windows Server 2012 File Information

File name

SHA1 hash

SHA256 hash

Windows8-RT-KB4020821-X64.msu

AE656B34B15996003E6EA26B9A97B7F34C942919

CC4ABBD3F887E640344E4E89D3F8646A4D665C0E50E7FF67977D0EF667626E38

File information The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows Server 2012 file information

 

Note: The MANIFEST files (.manifest) and MUM files (.mum) that are installed are not listed.

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

160,734

28-Apr-2017

22:47

Not applicable

Flash.ocx

25.0.0.171

28,249,048

28-Apr-2017

22:47

x64

Flashutil_activex.dll

25.0.0.171

702,936

28-Apr-2017

22:47

x64

Flashutil_activex.exe

25.0.0.171

973,784

28-Apr-2017

22:47

x64

Activex.vch

Not applicable

737,950

28-Apr-2017

22:47

Not applicable

Flash.ocx

25.0.0.171

21,805,528

28-Apr-2017

22:47

x86

Flashplayerapp.exe

25.0.0.171

835,040

28-Apr-2017

22:47

x86

Flashplayercplapp.cpl

25.0.0.171

177,120

28-Apr-2017

22:47

Not applicable

Flashutil_activex.dll

25.0.0.171

619,480

28-Apr-2017

22:47

x86

Flashutil_activex.exe

25.0.0.171

1,356,256

28-Apr-2017

22:47

x86

Windows 8.1 and Windows Server 2012 R2 File Information

File name

SHA1 hash

SHA256 hash

Windows8.1-KB4020821-X64.msu

E75817F6D9D75107704002FF9C5BF643A32ADFEA

64B67642E06E28B6EFB3556AD40C6D5707BB6DC3077FD86E49FE4E81626F106D

Windows8.1-KB4020821-ARM.msu

68962F2183A60F523511ABAE2B1166F9CC814454

62CF06F3A5953E138D62C4DB6761618BF54F1B4EBF069CE90C4BDBBE216972AB

Windows8.1-KB4020821-X86.msu

3723CF7FBE046BFC5F4F37ABA91ABA54E3C66668

B374A057C19F7E3DF2EC69BFE90FB95FA59BFEA4179BFFDEA095EF95D7DC06AE

File information The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows 8.1, Windows RT 8.1 and Windows Server 2012 R2 file information

Note: The MANIFEST files (.manifest) and MUM files (.mum) that are installed are not listed.

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

160,734

28-Apr-2017

22:44

Not applicable

Flash.ocx

25.0.0.171

28,249,592

28-Apr-2017

22:44

x64

Flashutil_activex.dll

25.0.0.171

703,480

28-Apr-2017

22:44

x64

Flashutil_activex.exe

25.0.0.171

974,328

28-Apr-2017

22:44

x64

Activex.vch

Not applicable

737,950

28-Apr-2017

22:44

Not applicable

Flash.ocx

25.0.0.171

21,806,072

28-Apr-2017

22:44

x86

Flashplayerapp.exe

25.0.0.171

835,576

28-Apr-2017

22:44

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

28-Apr-2017

22:44

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

28-Apr-2017

22:44

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

28-Apr-2017

22:44

x86

File name

File version

File size

Date

Time

Platform

Flash.ocx

25.0.0.171

18,784,248

28-Apr-2017

22:44

Not applicable

Flashplayerapp.exe

25.0.0.171

814,584

28-Apr-2017

22:44

Not applicable

Flashplayercplapp.cpl

25.0.0.171

163,320

28-Apr-2017

22:44

Not applicable

Flashutil_activex.dll

25.0.0.171

545,784

28-Apr-2017

22:44

Not applicable

Flashutil_activex.exe

25.0.0.171

833,016

28-Apr-2017

22:44

Not applicable

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

737,950

28-Apr-2017

22:44

Not applicable

Flash.ocx

25.0.0.171

21,806,072

28-Apr-2017

22:44

x86

Flashplayerapp.exe

25.0.0.171

835,576

28-Apr-2017

22:44

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

28-Apr-2017

22:44

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

28-Apr-2017

22:44

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

28-Apr-2017

22:44

x86

Windows 10 RTM File Information

File name

SHA1 hash

SHA256 hash

Windows10.0-KB4020821-X64.msu

78BE6D335926F66544F7D4A3A3E024962F6DF2C9

E2C6A138ACB35EA4D8F700CB3420AB9330F80E63328F2CC0932BAA5050597B3A

Windows10.0-KB4020821-X86.msu

643F7F77016AB870F0EBDD038E7058B869F5AE3C

806FDB95EB42F1DA4F4926EDFB0A4083A2C65653BADAF095EBCEB1F19C9E88F5

File information The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows 10 file information

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

160,734

29-Apr-2017

00:39

Not applicable

Flash.ocx

25.0.0.171

28,249,592

29-Apr-2017

00:39

x64

Flashutil_activex.dll

25.0.0.171

703,480

29-Apr-2017

00:39

x64

Flashutil_activex.exe

25.0.0.171

974,328

29-Apr-2017

00:39

x64

Activex.vch

Not applicable

737,950

29-Apr-2017

00:39

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

00:39

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

00:39

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

00:39

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

00:39

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

00:39

x86

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

737,950

29-Apr-2017

00:39

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

00:39

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

00:39

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

00:39

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

00:39

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

00:39

x86

Windows 10 Version 1511 File Information

File name

SHA1 hash

SHA256 hash

Windows10.0-KB4020821-x64.msu

B806AE9FBD43F3B5272931B4924571DFC0DC48CF

B24F0FF5EF02F7C8BF4E3D88C2DC46F6393204629FC0C2EFA9C3E81A73F6CBEF

Windows10.0-KB4020821-x86.msu

13FF7897ADA444F0975D56C8C7D09A1728D638EA

D1C5672DB44B57328198D6057B4989AC1E5F3D86EC29578376E8D7EFB06126DE

File information The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows 10 file information

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

160,734

29-Apr-2017

00:51

Not applicable

Flash.ocx

25.0.0.171

28,249,592

29-Apr-2017

00:51

x64

Flashutil_activex.dll

25.0.0.171

703,480

29-Apr-2017

00:51

x64

Flashutil_activex.exe

25.0.0.171

974,328

29-Apr-2017

00:51

x64

Activex.vch

Not applicable

737,950

29-Apr-2017

00:51

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

00:51

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

00:51

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

00:51

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

00:51

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

00:51

x86

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

737,950

29-Apr-2017

00:51

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

00:51

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

00:51

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

00:51

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

00:51

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

00:51

x86

Windows 10 Version 1607 and Windows Server 2016 File Information

File name

SHA1 hash

SHA256 hash

Windows10.0-KB4020821-X64.msu

F4D359A20B707CE63CF20539C451173C4D4CE1D1

14B9B47FD9646B0282A6D49BAF8EB7F17EE1CB56A0BD54C9CA480FD837E58518

Windows10.0-KB4020821-X86.msu

3126982EA147183296220D5BAC1F051455B0E3BB

032D91F2088B75E273DE832C4A4F566EF80F8124B85337B3917123B883B72223

File information The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows 10 file information

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

160,734

29-Apr-2017

00:59

Not applicable

Flash.ocx

25.0.0.171

28,249,592

29-Apr-2017

00:59

x64

Flashutil_activex.dll

25.0.0.171

703,480

29-Apr-2017

00:59

x64

Flashutil_activex.exe

25.0.0.171

974,328

29-Apr-2017

00:59

x64

Activex.vch

Not applicable

737,950

29-Apr-2017

00:59

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

00:59

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

00:59

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

00:59

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

00:59

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

00:59

x86

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

737,950

29-Apr-2017

00:59

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

00:59

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

00:59

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

00:59

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

00:59

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

00:59

x86

Windows 10 Version 1703 File Information

File name

SHA1 hash

SHA256 hash

Windows10.0-KB4020821-X64.msu

F864406D91F9C5DED327A3690C3FF000248F9EAB

668F67B4800EEFD31D9EA1A0CABC6C7A852B00C58A5431001CC1ACFB072E81A6

Windows10.0-KB4020821-X86.msu

AE35AC7B47C47508ABF580A544DC2F5D9BB7426B

B325A8956FAEE60AB2B30D623EC4830CED324CFCC7D27CCFF92359EAE6FF31C6

File information The English (United States) version of this software update installs files that have the attributes that are listed in the following tables.Windows 10 file information

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

160,734

29-Apr-2017

01:05

Not applicable

Flash.ocx

25.0.0.171

28,249,592

29-Apr-2017

01:05

x64

Flashutil_activex.dll

25.0.0.171

703,480

29-Apr-2017

01:05

x64

Flashutil_activex.exe

25.0.0.171

974,328

29-Apr-2017

01:05

x64

Activex.vch

Not applicable

737,950

29-Apr-2017

01:05

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

01:05

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

01:05

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

01:05

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

01:05

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

01:05

x86

File name

File version

File size

Date

Time

Platform

Activex.vch

Not applicable

737,950

29-Apr-2017

01:05

Not applicable

Flash.ocx

25.0.0.171

21,806,072

29-Apr-2017

01:05

x86

Flashplayerapp.exe

25.0.0.171

835,576

29-Apr-2017

01:05

x86

Flashplayercplapp.cpl

25.0.0.171

177,656

29-Apr-2017

01:05

Not applicable

Flashutil_activex.dll

25.0.0.171

620,024

29-Apr-2017

01:05

x86

Flashutil_activex.exe

25.0.0.171

1,356,792

29-Apr-2017

01:05

x86

Need more help?

Want more options?

Explore subscription benefits, browse training courses, learn how to secure your device, and more.

Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.