.NET Framework July 2020 Security and Quality Rollup Updates
.NET Framework Remote Code Execution Vulnerability
A remote code execution vulnerability exists in .NET Framework, Microsoft SharePoint, and Visual Studio 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, Microsoft SharePoint, and Visual Studio 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.
You may observe a patch install failure with Error: 0x643, or error code 1603, when attempting to install this update on a system with a proper Extended Security Update (ESU) license installed.
We are working on a resolution and will provide an update in an upcoming release.
Getting the Update
The Security and Quality Rollup is available via Windows Update, Windows Server Update Services, and Microsoft Update Catalog. The Security Only Update is available via Windows Server Update Services and Microsoft Update Catalog.
Microsoft Update Catalog
You can get the update via the Microsoft Update Catalog. For Windows 10, NET Framework 4.8 updates are available via Windows Update, Windows Server Update Services, Microsoft Update Catalog. Updates for other versions of .NET Framework are part of the Windows 10 Monthly Cumulative Update.