CuIISO4 + 2 FeIISO4 Cu0 + Fe2III(SO4)3

This is an oxidation-reduction (redox) reaction:

CuII + 2 e- Cu0 (reduction)

2 FeII - 2 e- 2 FeIII (oxidation)

CuSO4 is an oxidizing agent, FeSO4 is a reducing agent.