First-half tries from Luke Marshall and skipper Billy Burns made it three wins from four for Ulster in the Guinness Pro14 after they unconvincingly defeated Cardiff Blues 23-14 at Kingspan Stadium.
Scrum-half John Cooney kicked 13 points for the home side as they stayed ahead of the Blues, who scored second-half tries from Andy Summerhill and Will Boyde.
The Blues' other points were from Jarrod Evans, who kicked two conversions.
Ulster scored after just two minutes when flanker Sean Reidy charged down a kick from Jarrod Evans and then put Marshall away for a try which was converted by John Cooney.
Cooney landed a penalty five minutes later to make it 10-0 to the home side and this became 17-0 on 20 minutes when Burns saw a gap and darted through to grab a well-worked try, with Cooney adding the two points from the tee.
With Ulster now firmly in control, the expectation was that they would pile on the points against a fairly ragged Blues side but that failed to materialise as the home side were unable to score again in what remained of the half.
The Blues, though, also failed to take advantage of their frequent visits to Ulster's 22 due to the concession of penalties.
Ulster finished the half down to 14 men after Marshall's 39th minute yellow card with Cardiff again failing to take advantage with the half's final play.
The new half started badly for the home side as winger Aled Summerhill darted over from the side of a poorly defended ruck and though the score went to the TMO due to Morgan's apparent forward pass to Rory Thornton earlier in the move, the try somehow stood.
Evans converted and the Blues were back in it only for Ulster to win an immediate penalty, allowing Cooney to slot his second penalty.
Then three minutes before the hour 15-man Ulster coughed up their second try. This time it curiously came after Addison had shown lovely footwork to get out of his 22, only for the ball to be lost at the breakdown.
Sensing a gap at the back, the Blues kicked through and though Jason Harries was stopped on the line by Mattie Rea and Ludik, the Blues recycled and it was a run-in out on the right for Boyde which Evans converted.
Evans then missed a last minute penalty to bag a losing bonus point.