This is a fairly short and easy mission and thankfully won’t take too long to complete. At the start of this level, have all of your troops enter the alleyway to the right of the main street. Work your way along the alley here destroying enemy infantry units as you go. When you reach the end of the alleyawy, either order your soldiers (or to make things easier take control of them) to clear out the ASDs and turrets guarding the objective marker on the main street and to the right.
When it is relatively clear send ALL of your troops to the objective marker before planting the hacking device. Once planted, return to tactical view and target incoming enemy units. Once the timer is up on the hacking device a scene will play to end the mission.