Microsoft.Web.LibraryManager.Build starting to show security warnings

[leotsarev]

Describe the bug

Microsoft.Web.LibraryManager.Build starting to show security warnings

To Reproduce

1. Include <PackageReference Include="Microsoft.Web.LibraryManager.Build" Version="2.1.175" PrivateAssets="All" /> into the project
2. Build it using .NET SDK 9.0.100 or higher
3. Get

(..) warning NU1903: Package 'System.Private.Uri' 4.3.0 has a known high severity vulnerability, https://github.com/advisories/GHSA-5f2m-466j-3848
(..) warning NU1902: Package 'System.Private.Uri' 4.3.0 has a known moderate severity vulnerability, https://github.com/advisories/GHSA-x5qj-9vmx-7g6g
(..) warning NU1903: Package 'System.Private.Uri' 4.3.0 has a known high severity vulnerability, https://github.com/advisories/GHSA-xhfc-gr8f-ffwc    

Expected behavior

No security warnings

Additional context

NOTE: This is not a actual vulnerability
This is known problem in Nuget when using netstandart2 projects. dotnet/sdk#42651
It could be worked around by moving to CPM and pin System.Private.Uri version, but users are discouraged to reference System.Private.Uri directly, and it's frustrating for users to get this warning from official Microsoft package

It's recommended than:

• Version of nuget Microsoft.Web.LibraryManager.Cli provided that target modern .net (net9 or net8)
• System.Private.Uri is pinned by Microsoft.Web.LibraryManager.Cli to a non-vulnerable version

[jimmylewis]

I'm not reproducing this with a new web project:

dotnet new webapp
dotnet add package Microsoft.Web.LibraryManager.Build
dotnet build

and both libman packages (.Build and .Cli) should not bring transitive references to that package.

Can you include the output of dotnet nuget why x.csproj System.Private.Uri for your project?

[leotsarev]

dotnet nuget why won't show System.Private.Uri due to NuGet/Home#13718

I confirm that it won't reproduce on typical web project, but it will reproduce on Blazor if you are using
<Project Sdk="Microsoft.NET.Sdk.BlazorWebAssembly">.

There is minimal reproduction https://github.com/leotsarev/ReproduceLibManTest

[mrunks]

I too am seeing these warnings after upgrading one of my Blazor WebAssembly projects to .NET 9. Is there a way to suppress this warning ?

[leotsarev]

@mrunks

1. reference System.Private.Uri directly (latest version) -- it won´t change anything in runtime behavior
2. Add <NuGetAuditSuppress Include="https://github.com/advisories/GHSA-5f2m-466j-3848;https://github.com/advisories/GHSA-x5qj-9vmx-7g6g;https://github.com/advisories/GHSA-xhfc-gr8f-ffwc" /> to .csproj