Apparently..from the catechism:
“The Roman Pontiff... enjoys this infallibility in virtue of his office, when, as supreme pastor and teacher of all the faithful - who confirms his brethren in the faith - he proclaims by a definitive act a doctrine pertaining to faith or morals... This infallibility extends as far as the deposit of divine Revelation itself.” Pg. 235, #891
“In order to preserve the Church in the purity of the faith handed on by the apostles, Christ who is Truth willed to confer on her a share in his own infallibility. By a supernatural sense of faith the People of God, under the guidance of the Church’s livi ng magisterium, unfailingly adheres to this faith.” Pg. 235, #889