.NET May 2021 Updates – 5.0.6, 3.1.15, 2.1.28
Today, we are releasing the .NET May 2021 Updates. These updates contains reliability and security improvements. See the individual release notes for details on updated packages.
You can download 5.0.6 , 3.1.15, 2.1.28 versions for Windows, macOS, and Linux, for x86, x64, Arm32, and Arm64.
Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 5.0 and .NET Core 3.1.
This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
An elevation of privilege vulnerability exists in .NET 5.0 and .NET Core 3.1 when a user runs a single file application on Operating Systems based on Linux or macOS.
See release notes for Visual Studio compatibility for .NET Core 2.1 and .NET Core 3.1 and .NET 5.0.
OS Lifecycle update
Ubuntu 21.04 and Fedora 34 is now supported with the .NET 5.0.6, .NET Core 3.1.15 and .NET Core 2.1.28 update. The operating system support pages for .NET 5.0, .NET Core 3.1 and .NET Core 2.1 has been updated to reflect that.
Behavioral change in Asp.Net 2.1 Installers
Asp.Net 2.1.28 will now install side-by-side with Asp.Net 2.1.6 or earlier. It will still remove previously installed versions of Asp.Net that are 2.1.7 or newer. Users runnning the 2.1.28 Asp.Net Installer or 2.1.28 Hosting Bundle should manually uninstall any local versions of the Asp.Net runtime that are 2.1.6 or earlier.