The Argentina international joins Gus Poyet's revolution on Wearside, moving from Brazilian side Internacional to become the club's fourth January signing.
The 28-year-old only joined the Brazilian club in June 2013 but moves to the Premier League after a difficult spell in which he scored just four goals in 21 appearances.
Prior to the move to Internacional, Scocco led the line for Newell's Old Boys under current Barcelona manager Tata Martino, scoring 23 goals in 33 games to fire the Argentine outfit to the Torneo title.
Something of a nomad, he has previously played in Europe for AEK Athens and also moved to Al-Ain between his stints in Argentina and Brazil.
The Black Cats have been active in the transfer market as they look to avoid relegation and Scocco becomes Gus Poyet's fourth signing of the January window, following Oscar Ustari, Santiago Vergini and Marcos Alonso.
A 1-0 victory over Stoke on Wednesday night lifted Sunderland out of the relegation zone for the first time since August.