Success moved to English Premier League side Watford from Spanish side Granada in the 2016 summer transfer window.
However, he has struggled to establish himself with the Hornets, contributing just one goal in 19 appearances in his debut season due to persistent injury troubles.
Malaga have confirmed the signing of Success on the club's official Twitter handle, and he will team up with compatriot Brown Ideye who earlier moved to Malaga also on loan.
Watford new manager Javi Gracia brought in Gerard Deulofeu from Barcelona and was willing to allow Success leave on loan.
A move away from Vicarage road for Success could now bring him into Gernot Rohr's team for the upcoming FIFA World Cup.
Malaga would hope Success can replicate the form he showed while in Spain with Granada that earned him a move to Watford.