.NET March 2026 security Updates - .NET 10.0.4, .NET 9.0.14, .NET 8.0.25

[rbhanda]

.NET March 2026 Update

Release Notes

• 10.0.4
• 9.0.14
• 8.0.25

Status

Asset Type	10.0.4	9.0.14	8.0.25	Notes
Installers/Binaries	✅	✅	✅
Container Images (Linux)	✅	✅	✅
Container Images (Windows)	✅	✅	✅
Winget Packages
Linux Installers (Microsoft distribution)			The list below refers to the Microsoft-provisioned feeds (packages.microsoft.com) and does not in any way represent direct availability in distros (eg RHEL, Fedora).
Debian 12	✅	✅	✅
OpenSUSE 15 ✅		✅	✅
Rocky 9	✅	✅	✅
Ubuntu 20.04 ✅	✅	✅
Ubuntu 22.04	✅	✅	✅

Issues

Please report any issues you find either by responding to this issue, creating a new issue or creating a new issue in one of the following repos:

• ASP.NET Core: dotnet/aspnetcore
• Entity Framework Core: dotnet/efcore
• .NET CLI/SDK dotnet/sdk
• .NET runtime dotnet/runtime
• Winforms: dotnet/winforms
• WPF: dotnet/wpf
• NuGet: nuget/home
• Containers: dotnet/dotnet-docker
• Winget: microsoft/winget-pkgs

known issue

10.0.4: We have a known issue in .NET 10.0.4 where debugging is broken for customer on macOS using VS Code. This is a regression and is unrelated to the security fixes. To fix the developer experience, we will ship an OOB .NET 10.0.5 non security release on 12th March 2026. You will only need this patch if you are on macOS using VS code for debugging.

[reduckted]

Why wasn't the fix for dotnet/runtime#124369 included in 10.0.4? Can it be included in an OOB release? While that fix is not released, I cannot apply security updates. I'm already stuck on 10.0.1 because of it. I don't want to miss out on four months of security fixes.

[xialiadnv]

new dotnet is not capatible with msbuild version 17.14.40.60911.
release note does not mention about not supporting msbuild version 17

partial logs below got from azure pipeline, with MSBuild@1 task

Build started 3/11/2026 11:24:48 AM.

Project "C:\a\1\s\SpiLegacy\PIMSAll.sln" on node 1 (default targets).
ValidateSolutionConfiguration:
  Building solution configuration "Release|Any CPU".
##[error]PIMSWebCommon\PIMSWebCommon\PIMSWebCommon.csproj(0,0): Error : Could not resolve SDK "Microsoft.NET.Sdk". Exactly one of the probing messages below indicates why we could not resolve the SDK. Investigate and resolve that message to correctly specify the SDK.
  Version 10.0.200 of the .NET SDK requires at least version 18.0.0 of MSBuild. The current available version of MSBuild is 17.14.40.60911. Change the .NET SDK specified in global.json to an older version that requires the MSBuild version currently available.
  The NuGetSdkResolver did not resolve this SDK because there was no version specified in the project or global.json.
  MSB4276: The default SDK resolver failed to resolve SDK "Microsoft.NET.Sdk" because directory "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\MSBuild\Sdks\Microsoft.NET.Sdk\Sdk" did not exist.

workaround is set dotnet version to 10.0.103

additional:

azure devops windows agent does not have msbuild 18

##[warning]Unable to find MSBuild version '18.0' for architecture 'x64'. Falling back to version '17.0'.

[paolo-fullone]

I have a project using Fsharp.Core 10.0.100 in a csproj, when I inspect the DLL it refers to FSharp.Core, Version=11.0.0.0 and my project does not build.

I reverted the sdk to 10.0.103 [C:\Program Files\dotnet\sdk] and now it does build.

[scharnyw]

new dotnet is not capatible with msbuild version 17.14.40.60911. release note does not mention about not supporting msbuild version 17

partial logs below got from azure pipeline, with MSBuild@1 task

Build started 3/11/2026 11:24:48 AM.

Project "C:\a\1\s\SpiLegacy\PIMSAll.sln" on node 1 (default targets).
ValidateSolutionConfiguration:
  Building solution configuration "Release|Any CPU".
##[error]PIMSWebCommon\PIMSWebCommon\PIMSWebCommon.csproj(0,0): Error : Could not resolve SDK "Microsoft.NET.Sdk". Exactly one of the probing messages below indicates why we could not resolve the SDK. Investigate and resolve that message to correctly specify the SDK.
  Version 10.0.200 of the .NET SDK requires at least version 18.0.0 of MSBuild. The current available version of MSBuild is 17.14.40.60911. Change the .NET SDK specified in global.json to an older version that requires the MSBuild version currently available.
  The NuGetSdkResolver did not resolve this SDK because there was no version specified in the project or global.json.
  MSB4276: The default SDK resolver failed to resolve SDK "Microsoft.NET.Sdk" because directory "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\MSBuild\Sdks\Microsoft.NET.Sdk\Sdk" did not exist.

workaround is set dotnet version to 10.0.103

additional:

azure devops windows agent does not have msbuild 18

##[warning]Unable to find MSBuild version '18.0' for architecture 'x64'. Falling back to version '17.0'.

IMO this should probably be mentioned in the breaking changes. Although it was never officially mentioned that msbuild 17 supports .NET 10, it did work before this upgrade.