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 Server 2012 R2 (KB4514599)

Summary

An elevation of privilege vulnerability exists when the .NET Framework common language runtime (CLR) allows file creation in arbitrary locations. An attacker who successfully exploited this vulnerability could write files to folders that require higher privileges than what the attacker already has.

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

• CVE-2019-1142

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.

Additional information about this update

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

• 4514350 Description of the Security Only Update for .NET Framework 3.5 for Windows 8.1 and Server 2012 R2 (KB4514350)

• 4514341 Description of the Security Only Update for .NET Framework 4.5.2 for Windows 8.1 and Server 2012 R2 (KB4514341)

• 4514338 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 Server 2012 R2 (KB4514338)

• 4514331 Description of the Security Only Update for .NET Framework 4.8 for Windows 8.1 and Server 2012 R2 (KB4514331)

Information about protection and security

• Protect yourself online: Windows Security support

• Learn how we guard against cyber threats: Microsoft Security