This also applies to:

  • Microsoft .NET Framework 3.5

Summary

This security update resolves a vulnerability in Microsoft .NET Framework that could allow remote code execution when .NET Framework processes untrusted input. An attacker who successfully exploits this vulnerability in software by using .NET Framework could take control of an affected system. The attacker could then install programs; view, change, or delete data; or create new accounts that have full user rights. Users whose accounts are configured to have fewer user rights on the system could be less affected than users who operate with administrative user rights.

To exploit the vulnerability, an attacker would first have to convince the user to open a malicious document or application.

This security update addresses the vulnerability by correcting how .NET Framework validates untrusted input.

To learn more about this vulnerability, see Microsoft Common Vulnerabilities and Exposures CVE-2018-8421.

Important

  • All updates for Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2 require that update KB 2919355 is installed. We recommend that you install update KB 2919355 on your Windows 8.1-based, Windows RT 8.1-based, or Windows Server 2012 R2-based computer so that you receive updates in the future.

  • 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 need before you install this update. For more information, see Add language packs to Windows.

Additional information about this security update

For more information about this security update as it relates to Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2, see the following article in the Microsoft Knowledge Base:

4457920 Security and Quality Rollup updates for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1 and 4.7.2 for Windows 8.1, RT 8.1 and Server 2012 R2 (KB 4457920)

Known issues

After the September 2018 .NET Framework security update is applied to resolve CVE-2018-8421 (.NET Framework remote code execution vulnerability), SharePoint out-of-the-box workflows stop working.

For more information about this known issue, see the following article in the Microsoft Knowledge Base:

4465015 SharePoint Workflows stop working after you install .NET security updates for CVE-2018-8421

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.

Method 2: Windows Software Update Services (WSUS)

On your WSUS server, follow these steps:

  1. Select Start, select Administrative Tools, and then select Microsoft Windows Server Update Services 3.0.

  2. Expand ComputerName, and then select Action.

  3. Select Import Updates.

  4. WSUS opens a browser window in which you may be prompted to install an ActiveX control. Install the ActiveX control to continue.

  5. After the ActiveX control is installed, you see the Microsoft Update Catalog screen. Type 4457915 in the Search box, and then select Search.

  6. Locate the .NET Framework packages that match the operating systems, languages, and processors in your environment. Select Add to add them to your basket.

  7. After you select all the packages that you need, select View Basket.

  8. To import the packages to your WSUS server, select Import.

  9. After the packages are imported, select Close to return to WSUS.

The updates are now available for installation through WSUS.

Update deployment information

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

20180911 Security update deployment information: September 11, 2018

Update removal information

Note We do not recommend that you remove any security update. To remove this update, use the Programs and Features item in Control Panel.

Update restart information

This update does not require a system restart after you apply it unless files that are being updated are locked or are being used.

Update replacement information

This update replaces previously released updates KB4345592 and KB 4346082.

File information

File hash

File name

SHA1 hash

SHA256 hash

Windows8.1-KB4457045-x86.msu

2C5574D3EEAFE76CB407EC02CD601938F9C4AE66

33B061F9B35EE3F47B5208B74433F497B7A6C6CFEF25BC3F55BBCD91C58B8761

Windows8.1-KB4457045-x64.msu

3BF25E0EB158FD0A2AFC4179E34D356EAB936EC1

941576FED951ADDE6637807C3919772D0EB0FDD6D16CB2CBD28584087909DC76

File attributes for all supported x86-based systems

The English (United States) version of this update installs files that have the attributes that are listed in the following tables. The dates and times for these files are listed in Coordinated Universal Time (UTC). The dates and times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and times may change when you perform certain operations on the files.

File name

File version

File size

Date

Time

presentationframework.dll

3.0.6920.8773

5,283,840

30-Mar-2017

13:15

reachframework.dll

3.0.6920.8773

532,480

30-Mar-2017

13:15

smdiagnostics.dll

3.0.4506.8803

110,592

17-Jul-2018

13:13

smsvchost.exe

3.0.4506.8803

129,664

17-Jul-2018

13:13

system.data.sqlxml.dll

2.0.50727.8773

745,472

12-Dec-2017

13:09

system.identitymodel.dll

3.0.4506.8803

446,464

17-Jul-2018

13:13

system.management.dll

2.0.50727.8766

389,120

12-Jul-2017

13:11

system.runtime.remoting.dll

2.0.50727.8771

307,200

31-Aug-2017

13:17

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

13:13

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

13:13

system.security.dll

2.0.50727.8784

274,432

28-Mar-2018

13:15

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

13:13

system.servicemodel.washosting.dll

3.0.4506.8803

32,768

17-Jul-2018

13:13

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

13:13

system.web.regularexpressions.dll

2.0.50727.8762

98,304

22-Apr-2017

13:09

system.workflow.activities.dll

3.0.4203.8811

1,142,784

10-Aug-2018

13:11

system.workflow.componentmodel.dll

3.0.4203.8811

1,630,208

10-Aug-2018

13:11

system.workflow.runtime.dll

3.0.4203.8811

540,672

10-Aug-2018

13:11

system.xml.dll

2.0.50727.8773

2,056,192

12-Dec-2017

13:09

system.dll

2.0.50727.8791

3,207,168

11-Jul-2018

13:11

windowsbase.dll

3.0.6920.8773

1,257,472

30-Mar-2017

13:15

big5.nlp

66,728

07-Nov-2017

17:46

bopomofo.nlp

82,172

07-Nov-2017

17:46

ksc.nlp

116,756

07-Nov-2017

17:46

mscorlib.dll

2.0.50727.8793

4,554,752

24-Jul-2018

13:10

normidna.nlp

59,342

07-Nov-2017

17:46

normnfc.nlp

45,794

07-Nov-2017

17:46

normnfd.nlp

39,284

07-Nov-2017

17:46

normnfkc.nlp

66,384

07-Nov-2017

17:46

normnfkd.nlp

60,294

07-Nov-2017

17:46

prc.nlp

83,748

07-Nov-2017

17:46

prcp.nlp

83,748

07-Nov-2017

17:46

sortkey.nlp

262,148

07-Nov-2017

17:46

sorttbls.nlp

20,320

07-Nov-2017

17:46

xjis.nlp

28,288

07-Nov-2017

17:46

aspnet_wp.exe

2.0.50727.8762

31,384

22-Apr-2017

13:09

mscordacwks.dll

2.0.50727.8793

991,808

24-Jul-2018

13:10

mscorsvc.dll

2.0.50727.8793

231,992

24-Jul-2018

13:10

mscorwks.dll

2.0.50727.8793

5,948,472

24-Jul-2018

13:10

sos.dll

2.0.50727.8793

391,216

24-Jul-2018

13:10

webengine.dll

2.0.50727.8762

437,400

22-Apr-2017

13:09

wminet_utils.dll

2.0.50727.8766

116,896

12-Jul-2017

13:11

presentationcore.dll

3.0.6920.8773

4,222,976

30-Mar-2017

13:15

presentationfontcache.exe.config

161

20-Aug-2015

13:24

wpfgfx_v0300.dll

3.0.6920.8773

1,737,888

30-Mar-2017

13:15

system.data.dll

2.0.50727.8762

2,975,744

22-Apr-2017

13:09

system.printing.dll

3.0.6920.8773

372,736

30-Mar-2017

13:15

system.web.dll

2.0.50727.8762

5,287,936

22-Apr-2017

13:09

servicemonikersupport.dll

3.0.4506.8803

18,096

17-Jul-2018

13:13

system.identitymodel.dll

3.0.4506.8803

446,464

17-Jul-2018

13:13

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

13:13

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

13:13

penimc.dll

3.0.6920.8773

68,752

30-Mar-2017

13:15

presentationframework.dll

3.0.6920.8773

5,283,840

30-Mar-2017

13:15

presentationhostdll.dll

3.0.6920.8773

131,248

30-Mar-2017

13:15

reachframework.dll

3.0.6920.8773

532,480

30-Mar-2017

13:15

windowsbase.dll

3.0.6920.8773

1,257,472

30-Mar-2017

13:15

system.workflow.activities.dll

3.0.4203.8811

1,142,784

10-Aug-2018

13:11

system.workflow.componentmodel.dll

3.0.4203.8811

1,630,208

10-Aug-2018

13:11

system.workflow.runtime.dll

3.0.4203.8811

540,672

10-Aug-2018

13:11

File attributes for all supported x64-based systems

The English (United States) version of this update installs files that have the attributes that are listed in the following tables. The dates and times for these files are listed in Coordinated Universal Time (UTC). The dates and times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and times may change when you perform certain operations on the files.

File name

File version

File size

Date

Time

big5.nlp

66,728

26-Oct-2017

16:05

bopomofo.nlp

82,172

26-Oct-2017

16:05

ksc.nlp

116,756

26-Oct-2017

16:05

mscorlib.dll

2.0.50727.8793

4,571,136

24-Jul-2018

13:11

normidna.nlp

59,342

26-Oct-2017

16:05

normnfc.nlp

45,794

26-Oct-2017

16:05

normnfd.nlp

39,284

26-Oct-2017

16:05

normnfkc.nlp

66,384

26-Oct-2017

16:05

normnfkd.nlp

60,294

26-Oct-2017

16:05

prc.nlp

83,748

26-Oct-2017

16:05

prcp.nlp

83,748

26-Oct-2017

16:05

sortkey.nlp

262,148

26-Oct-2017

16:05

sorttbls.nlp

20,320

26-Oct-2017

16:05

xjis.nlp

28,288

26-Oct-2017

16:05

aspnet_wp.exe

2.0.50727.8762

43,160

22-Apr-2017

13:08

mscordacwks.dll

2.0.50727.8793

1,758,784

24-Jul-2018

13:11

mscorsvc.dll

2.0.50727.8793

495,232

24-Jul-2018

13:11

mscorwks.dll

2.0.50727.8793

10,008,632

24-Jul-2018

13:11

sos.dll

2.0.50727.8793

486,008

24-Jul-2018

13:11

system.data.sqlxml.dll

2.0.50727.8773

745,472

29-Nov-2017

05:34

system.management.dll

2.0.50727.8766

389,120

12-Jul-2017

13:08

system.runtime.remoting.dll

2.0.50727.8771

307,200

31-Aug-2017

13:15

system.security.dll

2.0.50727.8784

274,432

28-Mar-2018

13:15

system.web.regularexpressions.dll

2.0.50727.8762

98,304

22-Apr-2017

13:08

system.xml.dll

2.0.50727.8773

2,056,192

29-Nov-2017

05:34

system.dll

2.0.50727.8791

3,207,168

11-Jul-2018

13:12

webengine.dll

2.0.50727.8762

746,648

22-Apr-2017

13:08

wminet_utils.dll

2.0.50727.8766

140,960

12-Jul-2017

13:08

presentationcore.dll

3.0.6920.8773

4,006,400

30-Mar-2017

13:15

presentationfontcache.exe.config

161

22-Aug-2015

13:27

wpfgfx_v0300.dll

3.0.6920.8773

2,256,032

30-Mar-2017

13:15

system.data.dll

2.0.50727.8762

3,150,336

22-Apr-2017

13:08

system.printing.dll

3.0.6920.8773

358,400

30-Mar-2017

13:15

system.web.dll

2.0.50727.8762

5,296,128

22-Apr-2017

13:08

servicemonikersupport.dll

3.0.4506.8803

20,144

17-Jul-2018

13:12

smdiagnostics.dll

3.0.4506.8803

94,208

17-Jul-2018

13:12

smsvchost.exe

3.0.4506.8803

117,376

17-Jul-2018

13:12

system.identitymodel.dll

3.0.4506.8803

405,504

17-Jul-2018

13:12

system.runtime.serialization.dll

3.0.4506.8803

847,872

17-Jul-2018

13:12

system.runtime.serialization.dll

3.0.4506.8803

847,872

17-Jul-2018

13:12

system.servicemodel.dll

3.0.4506.8803

5,337,088

17-Jul-2018

13:12

system.servicemodel.washosting.dll

3.0.4506.8803

32,768

17-Jul-2018

13:12

system.servicemodel.dll

3.0.4506.8803

5,337,088

17-Jul-2018

13:12

penimc.dll

3.0.6920.8773

85,648

30-Mar-2017

13:15

presentationframework.dll

3.0.6920.8773

4,640,768

30-Mar-2017

13:15

presentationhostdll.dll

3.0.6920.8773

172,208

30-Mar-2017

13:15

reachframework.dll

3.0.6920.8773

532,480

30-Mar-2017

13:15

windowsbase.dll

3.0.6920.8773

1,118,208

30-Mar-2017

13:15

system.workflow.activities.dll

3.0.4203.8811

1,060,864

10-Aug-2018

13:11

system.workflow.componentmodel.dll

3.0.4203.8811

1,519,616

10-Aug-2018

13:11

system.workflow.runtime.dll

3.0.4203.8811

454,656

10-Aug-2018

13:11

presentationframework.dll

3.0.6920.8773

5,283,840

30-Mar-2017

13:15

reachframework.dll

3.0.6920.8773

532,480

30-Mar-2017

13:15

smdiagnostics.dll

3.0.4506.8803

110,592

17-Jul-2018

13:13

smsvchost.exe

3.0.4506.8803

129,664

17-Jul-2018

13:13

system.data.sqlxml.dll

2.0.50727.8773

745,472

12-Dec-2017

13:09

system.identitymodel.dll

3.0.4506.8803

446,464

17-Jul-2018

13:13

system.management.dll

2.0.50727.8766

389,120

12-Jul-2017

13:11

system.runtime.remoting.dll

2.0.50727.8771

307,200

31-Aug-2017

13:17

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

13:13

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

13:13

system.security.dll

2.0.50727.8784

274,432

28-Mar-2018

13:15

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

13:13

system.servicemodel.washosting.dll

3.0.4506.8803

32,768

17-Jul-2018

13:13

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

13:13

system.web.regularexpressions.dll

2.0.50727.8762

98,304

22-Apr-2017

13:09

system.workflow.activities.dll

3.0.4203.8811

1,142,784

10-Aug-2018

13:11

system.workflow.componentmodel.dll

3.0.4203.8811

1,630,208

10-Aug-2018

13:11

system.workflow.runtime.dll

3.0.4203.8811

540,672

10-Aug-2018

13:11

system.xml.dll

2.0.50727.8773

2,056,192

12-Dec-2017

13:09

system.dll

2.0.50727.8791

3,207,168

11-Jul-2018

13:11

windowsbase.dll

3.0.6920.8773

1,257,472

30-Mar-2017

13:15

big5.nlp

66,728

07-Nov-2017

17:46

bopomofo.nlp

82,172

07-Nov-2017

17:46

ksc.nlp

116,756

07-Nov-2017

17:46

mscorlib.dll

2.0.50727.8793

4,554,752

24-Jul-2018

13:10

normidna.nlp

59,342

07-Nov-2017

17:46

normnfc.nlp

45,794

07-Nov-2017

17:46

normnfd.nlp

39,284

07-Nov-2017

17:46

normnfkc.nlp

66,384

07-Nov-2017

17:46

normnfkd.nlp

60,294

07-Nov-2017

17:46

prc.nlp

83,748

07-Nov-2017

17:46

prcp.nlp

83,748

07-Nov-2017

17:46

sortkey.nlp

262,148

07-Nov-2017

17:46

sorttbls.nlp

20,320

07-Nov-2017

17:46

xjis.nlp

28,288

07-Nov-2017

17:46

aspnet_wp.exe

2.0.50727.8762

31,384

22-Apr-2017

13:09

mscordacwks.dll

2.0.50727.8793

991,808

24-Jul-2018

13:10

mscorsvc.dll

2.0.50727.8793

231,992

24-Jul-2018

13:10

mscorwks.dll

2.0.50727.8793

5,948,472

24-Jul-2018

13:10

sos.dll

2.0.50727.8793

391,216

24-Jul-2018

13:10

webengine.dll

2.0.50727.8762

437,400

22-Apr-2017

13:09

wminet_utils.dll

2.0.50727.8766

116,896

12-Jul-2017

13:11

presentationcore.dll

3.0.6920.8773

4,222,976

30-Mar-2017

13:15

presentationfontcache.exe.config

161

20-Aug-2015

13:24

wpfgfx_v0300.dll

3.0.6920.8773

1,737,888

30-Mar-2017

13:15

system.data.dll

2.0.50727.8762

2,975,744

22-Apr-2017

13:09

system.printing.dll

3.0.6920.8773

372,736

30-Mar-2017

13:15

system.web.dll

2.0.50727.8762

5,287,936

22-Apr-2017

13:09

servicemonikersupport.dll

3.0.4506.8803

18,096

17-Jul-2018

13:13

system.identitymodel.dll

3.0.4506.8803

446,464

17-Jul-2018

13:13

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

13:13

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

13:13

penimc.dll

3.0.6920.8773

68,752

30-Mar-2017

13:15

presentationframework.dll

3.0.6920.8773

5,283,840

30-Mar-2017

13:15

presentationhostdll.dll

3.0.6920.8773

131,248

30-Mar-2017

13:15

reachframework.dll

3.0.6920.8773

532,480

30-Mar-2017

13:15

windowsbase.dll

3.0.6920.8773

1,257,472

30-Mar-2017

13:15

system.workflow.activities.dll

3.0.4203.8811

1,142,784

10-Aug-2018

13:11

system.workflow.componentmodel.dll

3.0.4203.8811

1,630,208

10-Aug-2018

13:11

system.workflow.runtime.dll

3.0.4203.8811

540,672

10-Aug-2018

13:11

How to obtain help and support for this security update

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