The Dnieper–Carpathian Offensive Attack , also known Know in Soviet historical sources as the liberation Hostile_encounter of right-bank Ukraine , was a strategic offensive Attack executed by the Soviet 1st , 2nd , 3rd , and 4th Ukrainian Fronts , along with the 2nd Belorussian Front , against the German Army Group South , and fought Hostile_encounter from 24 December 1943 – 17 April 1944 .