/usr/lib/mono/xbuild/14.0/ is in mono-xbuild 4.6.2.7+dfsg-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/mono/xbuild/14.0/Imports/
/usr/lib/mono/xbuild/14.0/Imports/Microsoft.Common.props/
/usr/lib/mono/xbuild/14.0/Imports/Microsoft.Common.props/ImportBefore/
/usr/lib/mono/xbuild/14.0/Imports/Microsoft.Common.props/ImportBefore/Microsoft.NuGet.ImportBefore.props
/usr/lib/mono/xbuild/14.0/Microsoft.Common.props
/usr/lib/mono/xbuild/14.0/Microsoft.Common.targets/
/usr/lib/mono/xbuild/14.0/Microsoft.Common.targets/ImportAfter/
/usr/lib/mono/xbuild/14.0/Microsoft.Common.targets/ImportAfter/Microsoft.NuGet.ImportAfter.targets
/usr/lib/mono/xbuild/14.0/bin/
/usr/lib/mono/xbuild/14.0/bin/MSBuild/
/usr/lib/mono/xbuild/14.0/bin/MSBuild/Microsoft.Build.CommonTypes.xsd
/usr/lib/mono/xbuild/14.0/bin/MSBuild/Microsoft.Build.Core.xsd
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Build.Engine.dll
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Build.Framework.dll
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Build.Tasks.Core.dll
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Build.Utilities.Core.dll
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Build.dll
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Build.xsd
/usr/lib/mono/xbuild/14.0/bin/Microsoft.CSharp.targets
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Common.targets
/usr/lib/mono/xbuild/14.0/bin/Microsoft.Common.tasks
/usr/lib/mono/xbuild/14.0/bin/Microsoft.VisualBasic.targets
/usr/lib/mono/xbuild/14.0/bin/Mono.XBuild.Tasks.dll
/usr/lib/mono/xbuild/14.0/bin/xbuild.exe
/usr/lib/mono/xbuild/14.0/bin/xbuild.exe.config
/usr/lib/mono/xbuild/14.0/bin/xbuild.rsp