Does the infield fly rule apply to a bunted ball?

No, as long as it is a fair ball. Once the umpire signals the infield fly rule the batter is automatically out. However, if the ball is dropped and is ruled a foul ball, the umpire reverses his call and the batter continues his turn at bat. Nevertheless, the batter can not reach first from that batted ball. You will often find an umpire state "Infield fly, Batter is out if Fair". When the rule is in effect, the batter may not get on first base.