The newly-promoted outfit showed little sign of making the most of their numerical advantage following Isaac Hayden's controversial red card shortly after the hour mark, with Newcastle holding on as both teams picked up their first point of the campaign.
The match got off to a high-tempo start, and Newcastle were the first to test the keeper when Kenedy's low strike from just outside the area was collected at the second attempt by Etheridge.
It was Cardiff who created the best chance of the first half moments later, though, when Sol Bamba was left unmarked from a corner but could not get enough on his header as Ayoze Perez blocked it before it could trouble Martin Dubravka.
Newcastle responded with a chance of their own just a minute later when Perez stole in to nick possession off Joe Bennett and race into the box, but the angle was against him and Etheridge made the save.
The bright start soon fizzled out, though, and one of the main talking points of the opening 45 minutes arrived shortly after the half-hour mark when referee Craig Pawson missed a kick out from Kenedy, who was fortunate to avoid a straight red card.
It capped off a disappointing first half for the Chelsea loanee, who also failed to complete a single successful pass before the interval as Newcastle struggled to get going against their newly-promoted hosts.
Cardiff were also finding clear-cut chances difficult to come by from open play, with their best such opening seeing Kenneth Zohore glance his header wide of the target from Bennett's cross.
Jonjo Shelvey looked the most likely to make something happen for the visitors throughout the first half, and it was his deep cross which led to Newcastle's best chance of the half as Perez got on the end of it, only to see his volley thwarted by Etheridge.
Shelvey then tested the keeper himself with a free kick right on the stroke of half time, but Rafael Benitez will have been unhappy with his side's display in the opening 45 minutes and subsequently replaced the booked Javier Manquillo with Hayden during the interval.
Little changed for Newcastle at the start of the second half, though, and it was Cardiff who looked the most like scoring in the opening stages, with Zohore wasting a clear chance after peeling away from his marker inside the area.
The major talking point arrived in the 66th minute when Newcastle were reduced to 10 men, with Hayden being shown a contentious red card by Craig Pawson for a challenge from behind on Josh Murphy, a little over 20 minutes after being introduced as a half-time sub.
Cardiff struggled to make the most of a golden opportunity to pick up a priceless Premier League win, though, with debutant Harry Arter drilling one long-range strike wide before Zohore wasted two good sights of goal in quick succession due to unconvincing finishes.
Indeed, it looked as though the hosts would come away with nothing when Sean Morrison was penalised for a handball inside his own area in the 95th minute, but Etheridge made it two penalty saves from two games so far this season to deny Kenedy, who endured one of the worst individual performances in recent Premier League history.
The result sees both sides pick up their first point of the campaign, while also ending Cardiff's 10-match losing streak against Newcastle, which was both the Bluebird's worst-ever and Newcastle's best-ever run against a single opponent in league history.
Cardiff next take on Huddersfield Town, while Newcastle will renew their search for a first win of the season at home to Chelsea next Sunday.
CARDIFF (4-3-3): Etheridge; Ecuele Manga, Morrison, Bamba, Bennett; Camarasa (Reid 76'), Ralls, Arter; Hoilett (Paterson 83'), Zohore, Murphy (Mendez-Laing 78')
NEWCASTLE (4-4-1-1): Dubravka; Manquillo (Hayden 46'), Lascelles, Clark, Dummett; Ritchie (Murphy 70'), Shelvey, Diame, Kenedy; Perez (Muto 65'); Joselu