      "should return unmodified object": function(res) {
        assert.isObject(res);
        assert.isObject(res.a);
        assert.isString(res.a.b);
        assert.equal(res.a.b, 'c');
      },
NVD is only using a subset of CWE for mapping instead of the entire CWE, and the weakness type is not covered by that subset.