Unai Emery's men failed to impress despite largely controlling proceedings, though they benefited from Bruno Ecuele Manga's haplessness at the back for Aubameyang's penalty, and Lacazette put the game beyond Cardiff before Nathaniel Mendez-Laing's stoppage-time consolation.
After pre-match tributes to Cardiff's missing striker Emiliano Sala, the visitors gave a good account of themselves in a first half of few chances, looking just as lively as their hosts, though they were perhaps fortunate Ecuele Manga did not concede a spot-kick shortly before the interval.
The Gabonese defender failed to learn his lesson, however, finding himself penalised in the second period and his compatriot Aubameyang converted, before Lacazette put the result beyond doubt with a fine effort of his own.
Mendez-Laing pulled one back with an excellent left-footed finish, but it amounted to little.
Arsenal were quick out of the blocks and should have gone ahead in the second minute, but Neil Etheridge got a touch to Sead Kolasinac's cross and an unbalanced Lacazette failed to pounce quick enough, seeing his eventual effort blocked.
Cardiff wasted a good chance of their own soon after – Bobby Reid slicing a volley just wide after Mohamed Elneny inadvertently nudged the ball on.
As underwhelming as Arsenal's first-half display was, they were furious to not get a penalty just before the break, as Ecuele Manga escaped unpunished when catching Lacazette.
The Cardiff man was not so fortunate midway through the second period, however, as he clumsily sent Kolasinac tumbling in the box and the previously anonymous Aubameyang converted confidently.
Lacazette sealed the win seven minutes from the end with a fine goal not in keeping with the rest of the match, as he took up possession out on the right, darted inside and finished clinically past Etheridge after bursting into the box.
Mendez-Laing netted in style right at the end, bending a left-footed strike into the bottom-left corner, though it had little impact as Cardiff remain in the drop zone, three points from safety.
Ozil fails to add spark
Mesut Ozil was making his first Premier League start of 2019, even taking the captain's armband, however he failed to offer Arsenal a huge amount of creativity and rarely caught the eye before being withdrawn late on.
Kolasinac a constant threat
In a game generally devoid of quality, there were few standout performances. But Kolasinac on the left for Arsenal was a willing runner, causing Cardiff numerous problems and winning the penalty.
