Friday's contest at Ewood Park pitched together two sides harbouring promotion ambitions, with Cardiff eyeing an immediate return to the Premier League while the hosts seek to move on from the disappointment of missing out of the Championship play-offs last term.
It was the Welsh outfit who opened the scoring, Kenwyne Jones' header handing Ole Gunnar Solskjaer's side the advantage in the first half.
But Rovers drew level before the interval and did so in style courtesy of Cairney's excellent finish from outside the box.
The hosts thought they should have had a penalty in just the second minute, but Mark Hudson's handball was adjudged to be outside the area.
Cardiff, who won the title the last time they were in the second tier, threatened in the 14th minute when Jones' close-range header was tipped over the crossbar by Paul Robinson.
The striker was not to be denied, though, and opened the scoring four minutes later as he nodded home from Hudson's flick-on following Peter Whittingham's inviting set-piece delivery.
Blackburn had to soak up some pressure after that but found their rhythm to level five minutes before half-time, Cairney rifling home an excellent effort from 20 yards.
A rare moment of panic from the usually reliable David Marshall afforded Rudy Gestede an opportunity early in the second half, but his header was off target.
There were few chances of note from then on, with Blackburn particularly guilty of picking the wrong option in the final third.
Craig Conway spurned an opportunity to get one over on his former employers when the Scot was wayward with a stoppage-time free-kick and it ended all square.
