The hosts had the better of the chances at the KC Stadium but the Bluebirds battled back to snatch a point on a frustrating afternoon for Steve Bruce's men
Centre-half Davies put the hosts ahead after 40 minutes, his first for the club, but the visiting side made a notable improvement after half-time and managed to draw level through an excellent Whittingham finish.
The result leaves the Bluebirds with five points from four matches, with Steve Bruce's Tigers one point further back.
Cardiff made three changes to the team that drew against Everton last time out, with Joe Lewis handed a Premier League debut in goal after David Marshall injured his hip playing for Scotland midweek.
Scottish midfielder Don Cowie and defender Kevin Theophile-Catherine were also drafted in.
Hull City boss Steve Bruce was able to pick the same 11 that lost away to Manchester City after Allan McGregor overcame a groin injury.
The hosts almost took the lead inside the opening seven minutes, but an out of sorts Danny Graham failed to cap an excellent move when he skied over the bar from 10 yards.
The on-loan Sunderland forward has not scored in 20 top-flight appearances and when Sone Aluko's shot was parried by Lewis, he showed a complete lack of composure with the goal at his mercy.
Cardiff began to get a foothold in the game but grew frustrated as they failed to convert the possession into any clear-cut chances.
Fraizer Campbell in particular was advised by referee Robert Madley to calm down.
The ex-Manchester United man was booked after 19 minutes and he could have been sent off five minutes later when he led with his studs up into a challenge on Jake Livermore.
Aluko and Tom Huddlestone both had long-range shots within minutes of each other to remind Cardiff of the threat that they could pose - and the visitors' defence was eventually breached five minutes before the break.
A deep cross from Huddlestone enabled Davies to get in front of his man and head home from close range.
Malky Mackay brought on Nicky Maynard for the second half as he sought to plot a way back into the contest.
Although Maynard was not involved, Cardiff did pull level 15 minutes into the second period.
Whittingham showed admirable endeavour to get on the end of a pinpoint Cowie cross and he rifled his volley home, leaving McGregor with no chance.
Aluko was denied by an offside flag late on and Graham headed straight at Lewis deep in injury time to add to his frustration.