Massachusetts General Laws Part II. Real and Personal Property and Domestic Relations (Ch. 183-210) Ch. 206, § 9

If a mortgagee of real estate or an assignee of such mortgagee dies without having foreclosed the mortgage, the mortgaged property and the debt secured thereby shall be personal assets in the hands of his executor or administrator, and shall be administered and accounted for as such; and the executor or administrator shall have the same rights of entry and of action under said mortgage as the mortgagee or his assignee.