Simon Davies' second-half double followed a first-half strike from Gael Kakuta to deliver the Cottagers a deserved success at the Stadium of Light.
The Black Cats have a six-point gap to the relegation zone with three games remaining, but with none of their forwards expected to be fit before the end of the campaign, Steve Bruce will not be taking anything for granted yet.
With all of Sunderland's senior strikers injured, Bruce was forced to play midfielder Stephane Sessegnon as a lone centre-forward this afternoon, with Steed Malbranque playing on the Benin international's shoulder.
Realistically, the formation was the only one available, but perhaps predictably, it left the Black Cats short of attacking firepower.
Ahmed Elmohamady flashed a 14th-minute header past the post, but despite dominating possession, Sunderland failed to create another opening until Malbranque wasted a decent opportunity on the half-hour mark.
Philippe Senderos' clearance hit the Belgian, but after bursting beyond the covering defenders, Malbranque lofted a wasteful chip well wide of the target.
Fulham had created little at that stage, but three minutes later, the visitors claimed the lead. Bobby Zamora rolled the ball to Kakuta inside the 18-yard box, and after holding off Michael Turner, the Chelsea loanee calmly slotted the ball past Simon Mignolet.
Sunderland created two opportunities to equalise before the break, but both went begging as both Lee Cattermole and Jordan Henderson displayed profligacy in front of goal.
Cattermole side-footed a tame effort straight at Mark Schwarzer after playing a neat one-two with Sessegnon, before Henderson skewed a shot horribly wide after Phil Bardsley's cross evaded the entire Fulham defence in first-half stoppage time.
Another chance came went in the opening six minutes of the second half Sessegnon aiming a shot much too close to Schwarzer after wriggling into space on the edge of the area before Fulham also went close with a cross-shot from Eidur Gudjohnsen that was almost turned in by Zamora. The visitors were the brighter side for much of the second half, and they doubled their lead in the 62nd minute with a particularly well-worked goal.
Zamora released Steve Sidwell down the left-hand side, and after the former Chelsea midfielder pulled the ball back from the byline, Davies caressed a precise side-footed finish into the bottom corner.
Bruce's response was to introduce Anton Ferdinand from the bench and send Nedum Onuoha forward as an emergency centre-forward, but things rapidly got worse for the Black Cats when Fulham scored a third with 17 minutes left.
Zamora broke free down the right-hand side, Ferdinand and Simon Mignolet got into an almighty tangle after the striker delivered a low cross, and Davies was left with the simple task of tapping the loose ball into a gaping goalmouth.
SUNDERLAND (4-4-1-1): Mignolet; Elmohamady, Onuoha, Turner, Bardsley; Henderson (Lynch 76), Cattermole, Muntari (Ferdinand 66), Colback; Malbranque (Zenden 76); Sessegnon.
Subs (not used): Carson (gk), Mensah, Adams, Riveros.
FULHAM (4-4-2): Schwarzer; Baird, Senderos, Hughes, Salcido; Davies, Sidwell, Murphy (Etuhu 79), Kakuta (Greening 62); Gudjohnsen, Zamora (Johnson 79).
Subs (not used): Stockdale (gk), Kelly, Hoesen, Dembele.
Source: Northern Echo
Source: Northern Echo