Humphreys lets Munster off hook
Ulster's Ian Humphreys could not convert Nick Williams' late try as Munster moved to the top of the PRO12 League for at least 24 hours.
The men in red went 12 points behind before 21 points in 30 minutes gave them the four points.
Certainly, Ulster needed no second invitation to put their patterns into action, centre Stuart McCloskey bursting between two defenders for Donncha O'Callaghan to hand Ian Humphreys three points for not rolling away at the ruck.
Munster were uncharacteristically tentative in contact and wayward in their kicking game as Ulster countered more impressively through the air for Humphreys to double the lead from CJ Stander's side entry in the tenth minute.
It went from bad to worse when Paddy Butler obstructed Stuart Olding and O'Callaghan played the ball from an offside position for Humphreys to fire penalties for 12-0 at the end of the first quarter.
Munster had to halt their momentum. Stuart Olding's loose clearance went straight out on the full and Ian Keatley shot three for a high tackle by Humphreys on Gerhard van den Heever.
This was improved on the back of Nick Williams' indiscipline, conceding a petulant penalty, to allow Munster the front-foot for the slick hands of Keatley and Denis Hurley to put Robin Copeland over for 12-8 on the half hour.
The home side came out with renewed aggression in the second-half with Copeland's expert grab and burst from a lineout setting up field position.
He looked to have undermined this by miscontrolling the ensuing scrum ball only to confuse Ulster's defence long enough for Duncan Williams to fend off Paul Marshall and slide in at the corner.
Keatley converted from the left touchline and soon made a penalty for illegal work at the maul to take Munster out to 18-12 in the 52nd minute.
The one-way traffic continued when Keatley added three more when Sean Reidy was whistled for holding on under pressure from Denis Hurley.
Then, Ulster were given a lifeline from Stephen Archer's yellow card for taking out a lifter at a lineout ahead of Humphreys fifth penalty with ten minutes left on the clock.
Ulster suddenly had all the front-foot ball. Roger Wilson went close and Nick Williams made sire from no more than a metre for the try that Humphreys could not convert.