This also applies to:
- Microsoft .NET Framework 3.5
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This security update resolves a vulnerability in Microsoft .NET Framework that could allow remote code execution when .NET Framework processes untrusted input. An attacker who successfully exploits this vulnerability in software by using .NET Framework could take control of an affected system. The attacker could then install programs; view, change, or delete data; or create new accounts that have 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 first have to convince the user to open a malicious document or application.
This security update addresses the vulnerability by correcting how .NET Framework validates untrusted input.
To learn more about this vulnerability, see Microsoft Common Vulnerabilities and Exposures CVE-2018-8421.
Important
For more information about this security update as it relates to Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2, see the following article in the Microsoft Knowledge Base:
4457916 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 4457916)
After the September 2018 .NET Framework security update is applied to resolve CVE-2018-8421 (.NET Framework remote code execution vulnerability), SharePoint out-of-the-box workflows stop working.
For more information about this known issue, see the following article in the Microsoft Knowledge Base:
4465015 SharePoint Workflows stop working after you install .NET security updates for CVE-2018-8421
To get the stand-alone package for this update, go to the Microsoft Update Catalog.
On your WSUS server, follow these steps:
The updates are now available for installation through WSUS.
For deployment details for this security update, go to the following article in the Microsoft Knowledge Base:
20180911 Security update deployment information: September 11, 2018
Note We do not recommend that you remove any security update. To remove this update, use the Programs and Features item in Control Panel.
This update does not require a system restart after you apply it unless files that are being updated are locked or are being used.
This update does not replace any previously released update.
File name | SHA1 hash | SHA256 hash |
---|---|---|
Windows8.1-KB4457056-x86.msu | 04ABBCC751DAE38C8A5E67A98B20CD44425D9364 | 832C49EE9F17AAAE8D4F8D728B1FFF6B37D9365CB32D3DB22F202FB4EE696A0A |
Windows8.1-KB4457056-x64.msu | B8840809D4890369CC0002B95EBCD6746466CB7B | D280196000A0CE3416CD4156E6345E1EADB28D9D062367EDDB48403F006F249C |
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