The point would have felt like all three for the Bluebirds, though, as Anthony Pilkington struck in added time to level up a game that United dominated.
Cardiff's winning run may have ended at eight matches, but the draw extends their lead over Fulham to eight points in the race for second place.
United will argue that they deserved to claim all three points, having taken a 28th-minute lead through Leon Clarke and created numerous chances for a second, though a failure to build on their slender advantage would come back to haunt them.
John Lundstram failed to make the most of his side's first opportunity inside the opening five minutes, heading the ball straight at Neil Etheridge after being picked out in the centre by Enda Stevens.
Another United attempt, this time from returning Wales international Lee Evans, ended high over the bar soon after as the Blades enjoyed the better of the early exchanges.
United bagged the breakthrough goal just short of the half-hour mark through Clarke, as he ended his 10-match goal drought with a weak attempt that deflected off Bruno Ecuele Manga and trickled over the line.
Etheridge had better luck later in the half, with Clarke's next effort deflecting off Sean Morrison and into his hands, but the hosts should have doubled their tally before the break.
United continued to take control of things and squandered another glorious chance early in the second half, as David Brooks wanted too many touches of the ball when played through and was thwarted by Etheridge.
Cardiff, who face Wolverhampton Wanderers and Aston Villa in their next two matches, did start to show signs of life as the final half-hour approached.
In the space of 60 seconds, Madine nearly turned in Aron Gunnarsson's driven cross and Zohore's angled shot had to be lifted over the bar by Moore.
The Bluebirds have scored 12 goals in the final 10 minutes of matches this term, and their never-say-die spirit earned them another point here.
After Clarke failed to turn the ball past Etheridge at his near post, substitute Pilkington swept a volley into the far corner at the other end to prevent the hosts from entering the top six, while at the same time edging Cardiff ever closer to the Premier League.
SHEFFIELD UNITED (3-5-2): Moore; O'Connell, Stearman (Wright 69'), Basham; Baldock, Lundstram, Evans (Leonard 88'), Fleck, Stevens; Brooks (Donaldson 72'), Clarke
CARDIFF CITY (4-2-3-1): Etheridge; Mangala, Morrison, Bamba, Bennett; Gunnarsson, Grujic; Patterson, Hoilett (Wildschut 78'), Mendez-Laing (Madine 46'); Zohore (Pilkington 78')