كتب : Hatem Maher
Rainford Kalaba scored the precious winner eight minutes from time.
Earlier, Collins Mbesuma could have put the hosts in front but he wasted a 40th-minute penalty.
Zambia, who held Egypt to a 1-1 draw in Cairo in their group opener, are on top with four points.
Rwanda, who drew with Algeria in their previous game, remain on just a single point.
Egypt and Algeria will have a chance to go level on points with Zambia when they meet in the other group match in Blida on Sunday.