Ivan Cavaleiro ended Fulham's penalty curse as the Cottagers stunned Leicester to climb out of the relegation zone.
The striker's spot-kick, after Ademola Lookman's opener, gave Scott Parker's side a surprise 2-1 win at the King Power Stadium.
The Cottagers had missed their previous three penalties but they are now a point above the Premier League's drop zone.
Harvey Barnes grabbed a late consolation for the hosts while Youri Tielemans and Wesley Fofana hit the woodwork in the first half.
Leicester stay fourth, missing the chance to go level on points with Tottenham and Liverpool at the top.
Defeat also increased their home woes with the Foxes having lost three of their last four and they now face a 3,200-mile round trip to Ukraine for Thursday's Europa League clash with Zorya Luhansk.
Fulham, though, were good value for their win with Andre-Frank Anguissa, Cavaleiro and Ruben Loftus-Cheek all impressing.
They rode their luck in the first half but rarely looked troubled once Lookman opened the scoring.
Yet it would have been different had Leicester gone ahead after 19 minutes instead of hitting the woodwork twice in a matter of seconds.
Harrison Reed chopped down James Justin and James Maddison's free-kick struck the Cottagers' wall.
It fell for Tielemans on the edge of the area and his first-time strike flew through a crowd to hit the post with the rebound finding Fofana.
The defender was unmarked with just Alphonse Areola to beat but managed to lift his shot over the goalkeeper and onto the bar from six yards.
The Foxes briefly threatened to take control but, after Antonee Robinson fired straight at Kasper Schmeichel, Fulham snatched the lead on the half hour.
Anguissa took possession inside his own half and burst forward, slipping in Lookman as Fofana went to the ball.
The striker then comfortably beat Schmeichel for his second goal of the season and celebrated by lifting a Senegal shirt in tribute to former Fulham midfielder Papa Bouba Diop following his death over the weekend.
If the opener stunned the Foxes they were shell-shocked when Fulham grabbed a second eight minutes later.
Bobby Decordova-Reid went down under Christian Fuchs' challenge in the box only for play to continue. VAR stepped in and referee Simon Hooper awarded the spot-kick after consulting his screen.
Cavaleiro buried the penalty – three-and-a-half minutes after the initial foul – having missed from the spot in last week's defeat to Everton.
The Cottagers had missed five of their previous eight Premier League penalties.
Fulham reached the break unscathed – the first time they had a two-goal lead away in the Premier League at the interval in almost nine years.
Leicester boss Brendan Rodgers introduced Cengiz Under and Barnes but the visitors stood firm.
Loftus-Cheek even had a shot deflected over and Schmeichel denied Lookman a second with 16 minutes left.
The Foxes looked out of ideas before Barnes pulled a goal back with four minutes remaining, hammering in Jamie Vardy's knockdown, but Fulham held on.