Having earlier collected a fifth booking of the season to rule himself out of City's next game against Peterborough, captain Hudson headed the visitors into a 30th minute lead from Craig Noone's cross.
Bellamy, who counts Rovers among his vast collection of former clubs, struck the crossbar towards the end of a first half where Blackburn produced a woeful 45 minutes - a worryingly familiar theme of their recent outings.
One of Rovers' few bright sparks, on-loan Manchester United forward Josh King, brought them level in the 51st minute, only for Bellamy to restore Cardiff's advantage four minutes later.
Substitutes Mason and Kim completed Blackburn's misery, leaving Henning Berg to survey a fourth defeat from eight games in charge that leaves his side 15 points behind the leaders after 21 games and, perhaps more significantly, four shy of the play-off places ahead of the weekend fixtures.
The visitors started the brighter and after Jason Lowe's yellow-card challenge on Bellamy in the 29th minute and an associated bout of handbags, Peter Whittingham punted the resulting free-kick hopefully forward. Rovers could only clear as far as Noone and his left-footed delivery from the right was planted past Paul Robinson by Hudson.
As Rovers pressed forward, Bellamy raced clear of a vacant backline and clipped against the bar.
Kazim-Richards was introduced for Markus Olsson as Berg looked to spark fresh impetus at the break and the change proved to be inspiredas the Turkey international controlled a Rhodes' flick on and released King to slot under onrushing Cardiff goalkeeper David Marshall.
Moments later Kazim-Richards saw a rasping 20-yard effort deflected behind, but no sooner had Blackburn briefly assumed the ascendancy they were behind once more.
Again a long, hopeful free-kick was not dealt with and Bellamy finished emphatically after cleverly exchanging headers with Helguson.
In the 63rd minute Mauro Formica spurned a glorious opportunity for a second equaliser. Marshall saved magnificently after Etuhu's shot deflected off King's back but, when Rhodes selflessly cut the loose ball across, the Argentinian attacker should have done far better than to blaze against the top of the bar with the goal at his mercy.
Bellamy departed to applause from all sides of the ground and replacement Mason made the points safe six minutes from time, catching Grant Hanley flat-footed to slip Helguson's header on beyond Robinson.
Fellow replacement Kim then got in on the act, sweeping home Helguson's return ball after capitalising on a terrible pass from Scott Dann that served to sum up Blackburn's evening.