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.NET 9 Addresses NuGet Vulnerabilities in Preview 6

With new dev tooling security vulnerabilities publicized regularly, Microsoft's new .NET 9 Preview 6 addresses the problem in one specific area: NuGet packages used for sharing code libraries, tools and other assets in the .NET ecosystem.

NuGet vulnerabilities, or CVEs, are tracked here, and Microsoft has for years published mitigation guidance like "How to Scan NuGet Packages for Security Vulnerabilities."

The problems persist, however, and Microsoft is attacking them on many fronts, including dev tooling minutiae like NuGetAudit now raises warnings for vulnerabilities in transitive dependencies, an SDK update included in .NET 9 Preview 6, just released today (July 9).

"NuGetAudit, first added in .NET 8, provides warnings during restore if any packages used by your project have known vulnerabilities," Microsoft explained. "It requires a package source that provides a vulnerability database, so in practice you need to use https://api.nuget.org/v3/index.json as a package source, and we have plans to allow auditing without nuget.org as a package source. For more information on NuGet Audit, including all configuration options, see the documentation on NuGet Audit."

In the .NET 9 SDK in Preview 6, the default behavior of NuGetAudit has changed. Previously, only direct package references were reported by default (<NuGetAuditMode>direct</NuGetAuditMode>). Now the default is warnings on both direct and transitive packages (<NuGetAuditMode>all</NuGetAuditMode>) with known vulnerabilities.

The preview doesn't include much new major functionality or features, as Microsoft is nearing the final stages of .NET 9 development, which is scheduled for general availability in November.

The company publishes associated GitHub discussions about .NET 9 previews, with new ones including:

For those with an inclination to dig into the nitty-gritty details, more Microsoft guidance can be found in the release notes for different properties including:

The main dev effort can be tracked in What's new in .NET 9, last updated June 11. The company says it has a special focus on cloud-native apps and performance.

About the Author

David Ramel is an editor and writer at Converge 360.

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