The Penguins did all their scoring in the middle period to win their fifth straight game. Washington has dropped three in a row and remained stuck on an Eastern Conference-low two victories.
Mike Ribeiro gave Washington a first-period lead, but Pittsburgh scored on the power play three times during its big second stanza.
Malkin tied it 6:59 into the period and Pascal Dupuis put the Penguins in front with 7:11 left on a slap shot.
Crosby finished the outburst with a power-play goal that came just 22 seconds from the end of the period.
Marc-Andre Fleury made 23 saves for Pittsburgh. Michael Neuvirth opened in goal for the Capitals and gave up two goals on 11 shots. Holtby surrendered three goals on 17 shots.
2014: The Year in Music [PHOTOS]