Microsoft is updating its author-signing certificate starting September 23, 2026
.NET Blog published “Microsoft is updating its author-signing certificate starting September 23, 2026” by The NuGet Team on 2026-09-23. Here is what it covers and why it matters for NuGet developers.
What was announced From the source
.NET Blog published “Microsoft is updating its author-signing certificate starting September 23, 2026” by The NuGet Team on 2026-09-23.
The publisher summarises it as: “Starting September 23, 2026, Microsoft is updating the author-signing certificate used for NuGet packages. Customers using trusted signer policies or certificate fingerprint verification should add the new certificate as soon as possible.”
The post is organised into these sections:
- Who will be impacted?
- Allow the new Microsoft certificate
- Client policy
- Package verification
At a glance · NuGet
What was announcedWhy it mattersWho should careWhat to do next
Why it matters Analysis
NuGet is how .NET applications consume dependencies. Changes to the client, package sources or package policies affect restore reliability, supply-chain security and how packages are published.
Who should care Analysis
- All .NET developers who restore packages
- Package authors and maintainers
- Teams responsible for dependency and supply-chain security
What to do next Analysis
- Read the full post on .NET Blog for details, code samples and documentation links.
- Check your NuGet.config sources and package source mapping settings.
- Run
dotnet list package --vulnerableto audit dependencies.
Sources and further reading
- Original post on .NET Blog (original source)
Original: “Microsoft is updating its author-signing certificate starting September 23, 2026”, .NET Blog, published 23 Sep 2026, retrieved 16 Oct 2026. This article was generated from the official source using our structured templates and passed automated quality checks. Spotted a mistake? See our corrections policy.