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 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 Server 2012, see the following article in the Microsoft Knowledge Base:

4457919 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 Server 2012 (KB 4457919)

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 KB4345591 and KB 4346081.

File information

File hash

File name

SHA1 hash

SHA256 hash

Windows8-RT-KB4457042-x64.msu

3624D9B9B32E2D39359F297777344D98D8A3DA39

A73358BBBCF7D37187B9D9C3FB2814C4276E6DFD42D105153F41371EACC9038A

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

21-Nov-2017

07:23

bopomofo.nlp

82,172

21-Nov-2017

07:23

ksc.nlp

116,756

21-Nov-2017

07:23

mscorlib.dll

2.0.50727.8793

4,571,136

24-Jul-2018

15:10

normidna.nlp

59,342

21-Nov-2017

07:23

normnfc.nlp

45,794

21-Nov-2017

07:23

normnfd.nlp

39,284

21-Nov-2017

07:23

normnfkc.nlp

66,384

21-Nov-2017

07:23

normnfkd.nlp

60,294

21-Nov-2017

07:23

prc.nlp

83,748

21-Nov-2017

07:23

prcp.nlp

83,748

21-Nov-2017

07:23

sortkey.nlp

262,148

21-Nov-2017

07:23

sorttbls.nlp

20,320

21-Nov-2017

07:23

xjis.nlp

28,288

21-Nov-2017

07:23

aspnet_wp.exe

2.0.50727.8762

43,160

07-Apr-2017

13:09

mscordacwks.dll

2.0.50727.8793

1,758,784

24-Jul-2018

15:10

mscorsvc.dll

2.0.50727.8793

495,232

24-Jul-2018

15:10

mscorwks.dll

2.0.50727.8793

10,008,632

24-Jul-2018

15:10

sos.dll

2.0.50727.8793

486,008

24-Jul-2018

15:10

system.data.sqlxml.dll

2.0.50727.8773

745,472

01-Dec-2017

13:13

system.management.dll

2.0.50727.8766

389,120

12-Jul-2017

13:09

system.runtime.remoting.dll

2.0.50727.8771

307,200

31-Aug-2017

13:09

system.security.dll

2.0.50727.8784

274,432

27-Mar-2018

17:37

system.web.regularexpressions.dll

2.0.50727.8762

98,304

07-Apr-2017

13:09

system.xml.dll

2.0.50727.8773

2,056,192

01-Dec-2017

13:13

system.dll

2.0.50727.8791

3,207,168

12-Jul-2018

00:30

webengine.dll

2.0.50727.8762

746,648

07-Apr-2017

13:09

wminet_utils.dll

2.0.50727.8766

140,960

12-Jul-2017

13:09

presentationcore.dll

3.0.6920.8773

4,006,400

29-Mar-2017

13:09

presentationfontcache.exe.config

161

06-Jul-2012

20:06

wpfgfx_v0300.dll

3.0.6920.8773

2,256,032

29-Mar-2017

13:09

system.data.dll

2.0.50727.8762

3,150,336

06-Apr-2017

20:26

system.printing.dll

3.0.6920.8773

358,400

29-Mar-2017

13:09

system.web.dll

2.0.50727.8762

5,296,128

07-Apr-2017

13:09

servicemonikersupport.dll

3.0.4506.8803

20,144

17-Jul-2018

18:37

smdiagnostics.dll

3.0.4506.8803

94,208

17-Jul-2018

18:37

smsvchost.exe

3.0.4506.8803

117,376

17-Jul-2018

18:37

system.identitymodel.dll

3.0.4506.8803

405,504

17-Jul-2018

18:37

system.runtime.serialization.dll

3.0.4506.8803

847,872

17-Jul-2018

18:37

system.runtime.serialization.dll

3.0.4506.8803

847,872

17-Jul-2018

18:37

system.servicemodel.dll

3.0.4506.8803

5,337,088

17-Jul-2018

18:37

system.servicemodel.washosting.dll

3.0.4506.8803

32,768

17-Jul-2018

18:37

system.servicemodel.dll

3.0.4506.8803

5,337,088

17-Jul-2018

18:37

penimc.dll

3.0.6920.8773

85,648

29-Mar-2017

13:09

presentationframework.dll

3.0.6920.8773

4,640,768

29-Mar-2017

13:09

presentationhostdll.dll

3.0.6920.8773

172,208

29-Mar-2017

13:09

reachframework.dll

3.0.6920.8773

532,480

29-Mar-2017

13:09

windowsbase.dll

3.0.6920.8773

1,118,208

29-Mar-2017

13:09

system.workflow.activities.dll

3.0.4203.8811

1,060,864

10-Aug-2018

00:00

system.workflow.componentmodel.dll

3.0.4203.8811

1,519,616

10-Aug-2018

00:00

system.workflow.runtime.dll

3.0.4203.8811

454,656

10-Aug-2018

00:00

presentationframework.dll

3.0.6920.8773

5,283,840

29-Mar-2017

13:09

reachframework.dll

3.0.6920.8773

532,480

29-Mar-2017

13:09

smdiagnostics.dll

3.0.4506.8803

110,592

17-Jul-2018

18:37

smsvchost.exe

3.0.4506.8803

129,664

17-Jul-2018

18:37

system.data.sqlxml.dll

2.0.50727.8773

745,472

01-Dec-2017

13:05

system.identitymodel.dll

3.0.4506.8803

446,464

17-Jul-2018

18:37

system.management.dll

2.0.50727.8766

389,120

12-Jul-2017

13:09

system.runtime.remoting.dll

2.0.50727.8771

307,200

31-Aug-2017

13:08

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

18:37

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

18:37

system.security.dll

2.0.50727.8784

274,432

27-Mar-2018

17:37

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

18:37

system.servicemodel.washosting.dll

3.0.4506.8803

32,768

17-Jul-2018

18:37

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

18:37

system.web.regularexpressions.dll

2.0.50727.8762

98,304

07-Apr-2017

13:09

system.workflow.activities.dll

3.0.4203.8811

1,142,784

09-Aug-2018

23:59

system.workflow.componentmodel.dll

3.0.4203.8811

1,630,208

09-Aug-2018

23:59

system.workflow.runtime.dll

3.0.4203.8811

540,672

09-Aug-2018

23:59

system.xml.dll

2.0.50727.8773

2,056,192

01-Dec-2017

13:05

system.dll

2.0.50727.8791

3,207,168

12-Jul-2018

00:30

windowsbase.dll

3.0.6920.8773

1,257,472

29-Mar-2017

13:09

big5.nlp

66,728

21-Nov-2017

07:23

bopomofo.nlp

82,172

21-Nov-2017

07:23

ksc.nlp

116,756

21-Nov-2017

07:23

mscorlib.dll

2.0.50727.8793

4,554,752

24-Jul-2018

15:10

normidna.nlp

59,342

21-Nov-2017

07:23

normnfc.nlp

45,794

21-Nov-2017

07:23

normnfd.nlp

39,284

21-Nov-2017

07:23

normnfkc.nlp

66,384

21-Nov-2017

07:23

normnfkd.nlp

60,294

21-Nov-2017

07:23

prc.nlp

83,748

21-Nov-2017

07:23

prcp.nlp

83,748

21-Nov-2017

07:23

sortkey.nlp

262,148

21-Nov-2017

07:23

sorttbls.nlp

20,320

21-Nov-2017

07:23

xjis.nlp

28,288

21-Nov-2017

07:23

aspnet_wp.exe

2.0.50727.8762

31,384

07-Apr-2017

13:09

mscordacwks.dll

2.0.50727.8793

991,808

24-Jul-2018

15:10

mscorsvc.dll

2.0.50727.8793

231,992

24-Jul-2018

15:10

mscorwks.dll

2.0.50727.8793

5,948,472

24-Jul-2018

15:10

sos.dll

2.0.50727.8793

391,216

24-Jul-2018

15:10

webengine.dll

2.0.50727.8762

437,400

07-Apr-2017

13:09

wminet_utils.dll

2.0.50727.8766

116,896

12-Jul-2017

13:09

presentationcore.dll

3.0.6920.8773

4,222,976

29-Mar-2017

13:09

presentationfontcache.exe.config

161

06-Jul-2012

20:04

wpfgfx_v0300.dll

3.0.6920.8773

1,737,888

29-Mar-2017

13:09

system.data.dll

2.0.50727.8762

2,975,744

06-Apr-2017

20:26

system.printing.dll

3.0.6920.8773

372,736

29-Mar-2017

13:09

system.web.dll

2.0.50727.8762

5,287,936

07-Apr-2017

13:09

servicemonikersupport.dll

3.0.4506.8803

18,096

17-Jul-2018

18:37

system.identitymodel.dll

3.0.4506.8803

446,464

17-Jul-2018

18:37

system.runtime.serialization.dll

3.0.4506.8803

970,752

17-Jul-2018

18:37

system.servicemodel.dll

3.0.4506.8803

5,996,544

17-Jul-2018

18:37

penimc.dll

3.0.6920.8773

68,752

29-Mar-2017

13:09

presentationframework.dll

3.0.6920.8773

5,283,840

29-Mar-2017

13:09

presentationhostdll.dll

3.0.6920.8773

131,248

29-Mar-2017

13:09

reachframework.dll

3.0.6920.8773

532,480

29-Mar-2017

13:09

windowsbase.dll

3.0.6920.8773

1,257,472

29-Mar-2017

13:09

system.workflow.activities.dll

3.0.4203.8811

1,142,784

09-Aug-2018

23:59

system.workflow.componentmodel.dll

3.0.4203.8811

1,630,208

09-Aug-2018

23:59

system.workflow.runtime.dll

3.0.4203.8811

540,672

09-Aug-2018

23:59

How to obtain help and support for this security update

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