The result sees Luton lying in 15th place, equidistant between the play-off places and the relegation zone, ahead of this weekend's trip to Stoke City.
Speaking after the Cardiff game, Hatters boss Nathan Jones revealed: "I’m disappointed, I thought first half we were very good, we matched them all over, had the best chance with Collo (James Collins), then we had to reshuffle completely.
"That derailed us a little bit, as pulling Glen (Rea) out of the centre of the park (due to an injury-enforced reshuffle) was a big thing, because as he gives us that discipline and arguably their most talented player (Harry Wilson) is in there.
"Our three midfield players vacated the area for that, they were able to have knock down without anyone around him and then he scores from 25 yards, so I'm disappointed with the first goal.”
Here are today's biggest transfer stories and the latest team news involving Luton Town and the rest of the Championship, ahead of the midweek action:
1. Addicks eye Doughty windfall
Charlton owner Thomas Sandgaard has suggested the club stand to profit greatly from former play Alfie Doughty, should Stoke City eventually cash in on their new signing, revealing that the Addicks have a "very healthy" sell-on clause. (London News Online) Photo: Clive Rose
2. Dolan seals fresh Rovers deal
Blackburn Rovers' teenage winger Tyrhys Dolan is the latest youngster to commit his future to the club, signing a new three-and-a-half year deal. The announcement follows that of John Buckley's new deal earlier in the week. (BBC Sport) Photo: Nathan Stirk
3. Celtic boss condemns McClean's online trolls
Celtic manager Neil Lennon has hit out at those targeting Republic of Ireland international James McClean with online sectarian abuse, branding the behaviour as "absolutely scandalous" (Sky Sports) Photo: Alex Pantling
4. QPR boss demands further action to tackle racism
QPR boss Mark Warburton has branded footballers taking the knee as a "hollow gesture" and insisted that the sport "has to do more" to stamp out racism, as footballers continue to be targeted with online racist abuse. (Evening Standard) Photo: Richard Heathcote