Security Only Update for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB4534978)

A remote code execution vulnerability exists when the Microsoft .NET Framework fails to validate input properly. An attacker who successfully exploited this vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.

To learn more about the vulnerabilities, go to the following Common Vulnerabilities and Exposures (CVE).

• CVE-2020-0605
• CVE-2020-0606
• CVE-2020-0646

Important

• As a reminder to advanced IT administrators, updates to .NET Framework 3.5 for Windows 8.1 and Windows Server 2012 R2 should only be applied on systems where .NET Framework 3.5 is present and enabled. Customers who attempt to pre-install updates to .NET Framework 3.5 to offline images that do not contain the .NET Framework 3.5 product enabled will expose these systems to failures to enable .NET Framework 3.5 after the systems are online. For more extensive information about deploying .NET Framework 3.5, see Microsoft .NET Framework 3.5 Deployment Considerations.
• 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.

• 4532961 Description of the Security Only Update for .NET Framework 3.5 for Windows 8.1 and Windows Server 2012 R2 (KB4532961)
• 4532962 Description of the Security Only Update for .NET Framework 4.5.2 for Windows 8.1 and Windows Server 2012 R2 (KB4532962)
• 4532970 Description of the Security Only Update for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows 8.1 and Windows Server 2012 R2 (KB4532970)
• 4532951 Description of the Security Only Update for .NET Framework 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB4532951)

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