    it "should return a 403 if a user attempts to get at the _diagnostics path" do
      get "/message-bus/_diagnostics"
      last_response.status.must_equal 403
    end
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.