Probably 'Dr. Huey', flowers and leaves shown are like that one - and habit photo looks just like it. This is used by major American rose producers as a rootstock. It is prone to black spot and often has mosaic patterns in my area - where failed grafts have left a great many of these behind on local properties (either hybrid teas etc. grafted onto it and planted too high are being lost to rare dips below 10-15F or there is a graft compatibility issue that results in the eventual death of the scions).

If it were mine it would be removed.