In addition to the Roman Pontiff, the following can dispense from private vows for a just cause provided that a dispensation does not injure a right acquired by others: 1/ the local ordinary and the pastor with regard to all their subjects and even travelers; 2/ the superior of a religious institute or society of apostolic life if it is clerical and of pontifical right with regard to members, novices, and persons who live day and night in a house of the institute or society; 3/ those to whom the Apostolic See or the local ordinary has delegated the power of dispensing.
Source: Code of Canon Law (Vatican.va)