Sign in with Microsoft
Sign in or create an account.
Hello,
Select a different account.
You have multiple accounts
Choose the account you want to sign in with.

Applies to:

Microsoft .NET Framework 4.8

REMINDER Windows Server 2008 R2 SP1 have reached the end of mainstream support and are now in extended security update (ESU) support.

Starting in July 2020, there will no longer be optional, non-security releases (known as "C" releases) for this operating system. Operating systems in extended support have only cumulative monthly security updates (known as the "B" or Update Tuesday release).

Verify that you have installed the required updates listed in the How to get this update section before installing this update. 

Customers who have purchased the Extended Security Update (ESU) for on-premises versions of these operating systems must follow the procedures in KB4522133 to continue receiving security updates after extended support ends on January 14, 2020. For more information on ESU and which editions are supported, see KB4497181. For more information, see the ESU blog.

The April 9, 2024 update for Windows Server 2008 R2 SP1 includes security improvements in .NET Framework 4.8. We recommend that you apply this update as part of your regular maintenance routines. Verify that you have installed the required updates listed in the How to get this update section before installing this update.

Summary

CVE-2024-21409 - .NET Framework Remote Code Execution Vulnerability
This security update addresses a remote code execution vulnerability detailed in CVE-2024-21409.

.NET Framework Defense in Depth Vulnerability
This security update addresses an issue where version of the OSS zlib library is out of date.

.NET Framework Defense in Depth Vulnerability
This security update addresses an issue in AIA fetching process.

Additional information about this update

The following articles contain additional information about this update as it relates to individual product versions.

  • 5037127 Description of the Security Only Update for .NET Framework 3.5.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Server 2008 R2 SP1 (KB5037127)

Known issues in this update

Microsoft is not currently aware of any issues in this update.

How to get this update

Before installing this update

Prerequisite:

To apply this update, you must have .NET Framework 4.8 installed.

You must install the updates listed below and restart your device before installing the latest Rollup. Installing these updates improves the reliability of the update process and mitigates potential issues while installing the Rollup and applying Microsoft security fixes.

  1. The March 12, 2019 servicing stack update (SSU) (KB4490628). To get the standalone package for this SSU, search for it in the Microsoft Update Catalog. This update is required to install updates that are only SHA-2 signed.

  2. The latest SHA-2 update (KB4474419) released September 10, 2019 or newer update. If you are using Windows Update, the latest SHA-2 update will be offered to you automatically. This update is required to install updates that are only SHA-2 signed. For more information on SHA-2 updates, see 2019 SHA-2 Code Signing Support requirement for Windows and WSUS.

  3. To get this security update, you must reinstall the "Extended Security Updates (ESU) Licensing Preparation Package" (KB5016892) for Windows Server 2008 R2 SP1 that is dated August 8, 2022 even if you previously installed the ESU key. The ESU licensing preparation package will be offered to you from WSUS. To get the standalone package for ESU licensing preparation package, search for it in the Microsoft Update Catalog.

  4. After you install the items above, we strongly recommend that you install the latest SSU.

    ​​​​​​​For Windows Server 2008 R2 SP1, you must have the servicing stack update (SSU) (KB5017397) that is dated September 13, 2022 or later installed. For more information about the latest SSU updates, see ADV990001 | Latest Servicing Stack Updates.

    If you use Windows Update, the latest SSU will be offered to you automatically if you are an ESU customer. To get the standalone package for the latest SSU, search for it in the Microsoft Update Catalog. For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

  5. Download the ESU MAK add-on key from the VLSC portal and deploy and activate the ESU MAK add-on key. If you use the Volume Activation Management Tool  (VAMT) to deploy and activate keys, follow the instructions here.

    IMPORTANT You do not need an additional key for deployment of the following:

    • You do not need to deploy an additional ESU key for Azure virtual machines (VMs), Azure Stack HCI.

    • For other Azure products such as Azure VMWare, Azure Nutanix solution Azure Stack (Hub, Edge), or for bring-your-own images on Azure for Windows Server 2008 SP2, and Windows Server 2008 R2 SP1 you do need to deploy the ESU key.  The steps to install, activate, and deploy ESUs are the same for the fourth year of ESU coverage.

Install this update

Release Channel

Available

Next Step

Windows Update and Microsoft Update

No

See the other options below.

Microsoft Update Catalog

Yes

To get the standalone package for this update, go to the Microsoft Update Catalog website.

Windows Server Update Services (WSUS)

Yes

This individual .NET Framework product update will be installed, as applicable, by applying the operating system update. For more information about operating system updates see additional information about this update section.

Restart requirement

You may need to restart the computer after you apply this update if any affected files are being used. We recommend that you exit all .NET Framework-based applications before you apply this update.

Update deployment information

For deployment details for this security update, see the Deployments tab of the Microsoft Security Response Center (MSRC) Security Update Guide.

Update replacement information

This update replaces previously released updates KB5034687 and KB5034277.

File Information

x86

File name

File version

File size

Date

Time

Aspnet_perf.dll

4.8.4718.0

37,296

27-Mar-2024

21:32

aspnet_wp.exe

4.8.4718.0

41,000

27-Mar-2024

21:32

Placeholder.dll

4.8.4718.0

19,488

27-Mar-2024

21:32

VsVersion.dll

14.8.4718.0

12,736

27-Mar-2024

21:32

PenIMC2_v0400.dll

4.8.4718.0

100,800

27-Mar-2024

21:32

PresentationCore.dll

4.8.4718.0

3,678,144

27-Mar-2024

21:32

PresentationFramework.dll

4.8.4718.0

6,294,976

27-Mar-2024

21:32

PresentationFramework-SystemData.dll

4.8.4718.0

18,992

27-Mar-2024

21:32

PresentationHost_v0400.dll

4.8.4718.0

234,944

27-Mar-2024

21:32

PresentationHost_v0400.dll.mui

4.8.4718.0

78,880

27-Mar-2024

21:32

PresentationNative_v0400.dll

4.8.4718.0

924,096

27-Mar-2024

21:32

ServiceMonikerSupport.dll

4.8.4718.0

25,536

27-Mar-2024

21:32

SMDiagnostics.dll

4.8.4718.0

68,608

27-Mar-2024

21:32

System.Activities.dll

4.8.4718.0

1,528,904

27-Mar-2024

21:32

System.Core.dll

4.8.4718.0

1,551,328

27-Mar-2024

21:32

System.IdentityModel.dll

4.8.4718.0

1,090,448

27-Mar-2024

21:32

System.IdentityModel.Services.dll

4.8.4718.0

192,536

27-Mar-2024

21:32

System.Runtime.Serialization.dll

4.8.4718.0

1,049,672

27-Mar-2024

21:32

System.ServiceModel.Channels.dll

4.8.4718.0

152,096

27-Mar-2024

21:32

System.ServiceModel.Discovery.dll

4.8.4718.0

302,624

27-Mar-2024

21:32

System.ServiceModel.dll

4.8.4718.0

6,387,592

27-Mar-2024

21:32

System.ServiceModel.Internals.dll

4.8.4718.0

248,800

27-Mar-2024

21:32

System.ServiceModel.WasHosting.dll

4.8.4718.0

34,336

27-Mar-2024

21:32

System.Web.ApplicationServices.dll

4.8.4718.0

66,120

27-Mar-2024

21:32

System.Web.Extensions.dll

4.8.4718.0

1,845,240

27-Mar-2024

21:32

System.dll

4.8.4718.0

3,561,952

27-Mar-2024

21:32

System.Web.dll

4.8.4718.0

5,412,896

27-Mar-2024

21:32

System.Windows.Controls.Ribbon.dll

4.8.4718.0

744,992

27-Mar-2024

21:32

System.Xaml.dll

4.8.4718.0

634,256

27-Mar-2024

21:32

UIAutomationClient.dll

4.8.4718.0

172,576

27-Mar-2024

21:32

UIAutomationClientsideProviders.dll

4.8.4718.0

355,360

27-Mar-2024

21:32

UIAutomationProvider.dll

4.8.4718.0

43,040

27-Mar-2024

21:32

UIAutomationTypes.dll

4.8.4718.0

217,136

27-Mar-2024

21:32

webengine.dll

4.8.4718.0

20,400

27-Mar-2024

21:32

webengine4.dll

4.8.4718.0

565,792

27-Mar-2024

21:32

WindowsBase.dll

4.8.4718.0

1,300,512

27-Mar-2024

21:32

WPFFontCache_v0400.exe.mui

4.8.4718.0

13,248

27-Mar-2024

21:32

WPFFontCache_v0400.exe

4.8.4718.0

21,048

27-Mar-2024

21:32

wpfgfx_v0400.dll

4.8.4718.0

1,620,512

27-Mar-2024

21:32

x64

File name

File version

File size

Date

Time

Aspnet_perf.dll

4.8.4718.0

43,056

27-Mar-2024

21:52

Aspnet_perf.dll

4.8.4718.0

37,296

27-Mar-2024

21:32

aspnet_wp.exe

4.8.4718.0

46,520

27-Mar-2024

21:52

aspnet_wp.exe

4.8.4718.0

41,000

27-Mar-2024

21:32

VsVersion.dll

14.8.4718.0

12,720

27-Mar-2024

21:52

Placeholder.dll

4.8.4718.0

21,424

27-Mar-2024

21:52

Placeholder.dll

4.8.4718.0

19,488

27-Mar-2024

21:32

VsVersion.dll

14.8.4718.0

12,736

27-Mar-2024

21:32

PenIMC2_v0400.dll

4.8.4718.0

121,776

27-Mar-2024

21:52

PenIMC2_v0400.dll

4.8.4718.0

100,800

27-Mar-2024

21:32

PresentationCore.dll

4.8.4718.0

3,654,576

27-Mar-2024

21:52

PresentationCore.dll

4.8.4718.0

3,678,144

27-Mar-2024

21:32

PresentationFramework.dll

4.8.4718.0

6,294,976

27-Mar-2024

21:32

PresentationFramework-SystemData.dll

4.8.4718.0

18,992

27-Mar-2024

21:32

PresentationHost_v0400.dll

4.8.4718.0

303,536

27-Mar-2024

21:52

PresentationHost_v0400.dll.mui

4.8.4718.0

78,784

27-Mar-2024

21:52

PresentationHost_v0400.dll

4.8.4718.0

234,944

27-Mar-2024

21:32

PresentationHost_v0400.dll.mui

4.8.4718.0

78,880

27-Mar-2024

21:32

PresentationNative_v0400.dll

4.8.4718.0

1,165,344

27-Mar-2024

21:52

PresentationNative_v0400.dll

4.8.4718.0

924,096

27-Mar-2024

21:32

ServiceMonikerSupport.dll

4.8.4718.0

28,608

27-Mar-2024

21:52

ServiceMonikerSupport.dll

4.8.4718.0

25,536

27-Mar-2024

21:32

SMDiagnostics.dll

4.8.4718.0

68,608

27-Mar-2024

21:32

System.Activities.dll

4.8.4718.0

1,528,904

27-Mar-2024

21:32

System.Core.dll

4.8.4718.0

1,551,328

27-Mar-2024

21:32

System.IdentityModel.dll

4.8.4718.0

1,090,448

27-Mar-2024

21:32

System.IdentityModel.Services.dll

4.8.4718.0

192,536

27-Mar-2024

21:32

System.Runtime.Serialization.dll

4.8.4718.0

1,049,672

27-Mar-2024

21:32

System.ServiceModel.Channels.dll

4.8.4718.0

152,096

27-Mar-2024

21:32

System.ServiceModel.Discovery.dll

4.8.4718.0

302,624

27-Mar-2024

21:32

System.ServiceModel.dll

4.8.4718.0

6,387,592

27-Mar-2024

21:32

System.ServiceModel.Internals.dll

4.8.4718.0

248,800

27-Mar-2024

21:32

System.ServiceModel.WasHosting.dll

4.8.4718.0

34,336

27-Mar-2024

21:32

System.Web.ApplicationServices.dll

4.8.4718.0

66,120

27-Mar-2024

21:32

System.Web.Extensions.dll

4.8.4718.0

1,845,240

27-Mar-2024

21:32

System.dll

4.8.4718.0

3,561,952

27-Mar-2024

21:32

System.Web.dll

4.8.4718.0

5,400,496

27-Mar-2024

21:52

System.Web.dll

4.8.4718.0

5,412,896

27-Mar-2024

21:32

System.Windows.Controls.Ribbon.dll

4.8.4718.0

744,992

27-Mar-2024

21:32

System.Xaml.dll

4.8.4718.0

634,256

27-Mar-2024

21:32

UIAutomationClient.dll

4.8.4718.0

172,576

27-Mar-2024

21:32

UIAutomationClientsideProviders.dll

4.8.4718.0

355,360

27-Mar-2024

21:32

UIAutomationProvider.dll

4.8.4718.0

43,040

27-Mar-2024

21:32

UIAutomationTypes.dll

4.8.4718.0

217,136

27-Mar-2024

21:32

webengine.dll

4.8.4718.0

22,448

27-Mar-2024

21:52

webengine.dll

4.8.4718.0

20,400

27-Mar-2024

21:32

webengine4.dll

4.8.4718.0

676,288

27-Mar-2024

21:52

webengine4.dll

4.8.4718.0

565,792

27-Mar-2024

21:32

WindowsBase.dll

4.8.4718.0

1,300,512

27-Mar-2024

21:32

WPFFontCache_v0400.exe.mui

4.8.4718.0

13,248

27-Mar-2024

21:52

WPFFontCache_v0400.exe.mui

4.8.4718.0

13,248

27-Mar-2024

21:32

WPFFontCache_v0400.exe

4.8.4718.0

23,008

27-Mar-2024

21:52

WPFFontCache_v0400.exe

4.8.4718.0

21,048

27-Mar-2024

21:32

wpfgfx_v0400.dll

4.8.4718.0

2,052,016

27-Mar-2024

21:52

wpfgfx_v0400.dll

4.8.4718.0

1,620,512

27-Mar-2024

21:32

How to obtain help and support for this update

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.

Was this information helpful?

What affected your experience?
By pressing submit, your feedback will be used to improve Microsoft products and services. Your IT admin will be able to collect this data. Privacy Statement.

Thank you for your feedback!

×