Welcome to our combined .NET servicing updates for September 2025. Let’s get into the latest release of .NET & .NET Framework, here is a quick overview of what’s new in our servicing releases:
Security improvements
.NET and .NET Framework has been refreshed with the latest update as of September 05, 2025. This update contains non-security fixes.
This month you will find non-security fixes:
| .NET 8.0 | .NET 9.0 | |
|---|---|---|
| Release Notes | 8.0.20 | 9.0.9 |
| Installers and binaries | 8.0.20 | 9.0.9 |
| Container Images | images | images |
| Linux packages | 8.0.20 | 9.0.9 |
| Known Issues | 8.0 | 9.0 |
Release changelogs
- Runtime: 8.0.20 | 9.0.9
- Aspnetcore: 8.0.20 | 9.0.9
- SDK: 9.0.9 Share feedback about this release in the Release feedback issue.
.NET Framework September 2025 Updates
This month, there are no new security updates, but there are new non-security updates available. For recent .NET Framework servicing updates, be sure to browse our release notes for .NET Framework for more details.
See you next month
That’s it for this month, make sure you update to the latest service release today.
I find it impossible to determine whether patch releases have changes that would impact me, and whether I should update prod env runtimes.
The release notes section Notable Changes points to this blog post, which points back to the release notes.
The changelog points to GitHub issues, with various backports, including one MR with numerous backports commits in one, and including package updates.
The impact of updating the package dependencies is unclear and undocumented.
FYI the “SDK: 9.0.9” link is broken — it should be https://github.com/dotnet/sdk/issues?q=milestone%3A9.0.9%20is%3Aclosed%20label%3Aservicing-approved