The return duel will take place the following weekend in Sousse, Tunisia.
Pirates reached the Final by beating Al-Ahly 5-3 on aggregate, while Etoile edged Zamalek 5-4 across two legs in their last-four tie.
Meanwhile, Bucs' flight home from Egypt has been delayed.
The club said on Twitter: "The plane to Dubai has been delayed by 45 mins due to a Military flyover. The airport will be shutdown momentarily. We now board at 12H30."
Eric Tinkler and his squad were initially scheduled to arrive at OR Tambo Airport at 16h25 on Tuesday.