Microsoft .NET Framework 4.8
On July 23, 2020, update KB4565636 v2 was released to replace v1 for .NET Framework 4.8 for Windows 7 SP1 and Windows Server 2008 R2 SP1. The v1 update did not install for customers who had certain ESU configurations. The v2 update corrects the issue for customers who could not install the v1 update.
If you have already installed KB4565636 v1, no action is necessary.
To obtain KB4565636 v2, see the “How to obtain and install the update” section.
IMPORTANT Verify that you have installed the required updates listed in the How to get this update section before installing this update.
IMPORTANT Some customers who use Windows Server 2008 R2 SP1 and have activated their ESU multiple activation key (MAK) add-on before installing the January 14, 2020 updates might need to re-activate their key. Re-activation on the affected devices should only be required once. For information on activation, see this blog post.
IMPORTANT WSUS scan cab files will continue to be available for Windows 7 SP1 and Windows Server 2008 R2 SP1. If you have a subset of devices running these operating systems without ESU, they might show as non-compliant in your patch management and compliance toolsets.
IMPORTANT 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.
IMPORTANT Starting on January 15, 2020, a full-screen notification will appear that describes the risk of continuing to use Windows 7 Service Pack 1 after it reaches end of support on January 14, 2020. The notification will remain on the screen until you interact with it. This notification will only appear on the following editions of Windows 7 Service Pack 1:
- Home Basic.
- Home Premium.
- Professional. If you have purchased the Extended Security Update (ESU), the notification will not appear. For more information, see How to get Extended Security Updates for eligible Windows devices and Lifecycle FAQ-Extended Security Updates.
Note The notification will not appear on domain-joined machines or machines in kiosk mode.
IMPORTANT Starting in August, 2019, updates to .NET Framework 4.6 and above, for Windows Server 2008 R2 SP1, and Windows 7SP1, require SHA-2 Code signing support. Please make sure that you have all the latest Windows Updates before applying this update to avoid installation issues. For more detailed information about SHA-2 code signing support updates, please see KB 4474419.
A remote code execution vulnerability exists in .NET Framework when the software fails to check the source markup of XML file input. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the process responsible for deserialization of the XML content. To exploit this vulnerability, an attacker could upload a specially crafted document to a server utilizing an affected product to process content. The security update addresses the vulnerability by correcting how .NET Framework validates the source markup of XML content.
This security update affects how .NET Framework's System.Data.DataTable and System.Data.DataSet types read XML-serialized data. Most .NET Framework applications will not experience any behavioral change after the update is installed. For more information on how the update affects .NET Framework, including examples of scenarios which may be affected, please see the DataTable and DataSet security guidance document at https://go.microsoft.com/fwlink/?linkid=2132227.
To learn more about the vulnerabilities, go to the following Common Vulnerabilities and Exposures (CVE).
Additional information about this update
- 4566517 Description of the Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 7 SP1 and Windows Server 2008 R2 SP1 (KB4566517)
How to obtain and install the update
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.
- 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.
- The latest SHA-2 update (KB4474419) released September 10, 2019. 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.
- The Extended Security Updates (ESU) Licensing Preparation Package (KB4538483) released February 11, 2020. 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.
Install this update
|Release Channel||Available||Next Step|
|Windows Update and Microsoft Update||Yes||None. This update will be downloaded and installed automatically from Windows Update if you are an ESU customer.|
|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 update will automatically sync with WSUS if you configure Products and Classifications as follows:
Product: Windows 7 Service Pack 1, Windows Server 2008 R2 Service Pack 1,Windows Embedded Standard 7 Service Pack 1, Windows Embedded POSReady 7Classification: Security Updates
You must 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, go to the following article in the Microsoft Knowledge Base:
20200714 Security update deployment information: July 14, 2020
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.