Achraf Hakimi scored in the sixth minute for Morocco, whose run to the semi-final of the World Cup in Qatar 14 months ago has made them the team to beat at the tournament in the Ivory Coast.
But the Congolese squandered a first half penalty before substitute Silas Katompa swept home a deserved 76th minute equaliser at the Laurent Pokou Stadium.
The two other protagonists in the group – Tanzania and Zambia – were meeting later on Sunday at San Pedro.