Description of the Security Only update for .NET Framework 4.5.2 for Windows 8.1 and Server 2012 R2 (KB 4470491)

Summary

This security update resolves a vulnerability in Microsoft .NET Framework that could allow remote code execution when Microsoft .NET Framework doesn't validate input correctly. An attacker who successfully exploits this vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts that use 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 have to pass specific input to an application that uses susceptible .NET Framework methods.

This security update addresses the vulnerability by correcting how .NET Framework validates input.

To learn more about this vulnerability, see Microsoft Common Vulnerabilities and Exposures CVE-2018-8540.

Important

• All updates for Windows 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 security update

For more information about this security update as it relates to Windows 8.1 and Windows Server 2012 R2, see the following article in the Microsoft Knowledge Base:

4471983 Security Only 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 8.1 and Server 2012 R2 (KB 4471983)

How to obtain and install the update

File information

File hash

File attributes for all supported x86-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 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 attributes for all supported ARM-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.

How to obtain help and support for this security update

• Help for installing updates: Windows Update FAQ

• Protect yourself online and at home: Windows Security support

• Local support according to your country: International Support