Internacional, who drew the second leg 2-2 but lost 4-2 on aggregate, said they will appeal against the ban, which will keep the hot-headed D'Alessandro out until September 12.
The former River Plate, VfL Wolfsburg, Portsmouth, Real Zaragoza and San Lorenzo playmaker faced a possible two-year ban but the tribunal ruled he had not actually attacked any opponents.
"I don't know what's going on in my head right now ... It's not a good moment to talk. I don't want to speak so I don't say anything stupid," D'Alessandro was quoted as saying by Globo Sport as he left the tribunal.
Television footage of the match shows D'Alessandro, who had just been sent off, punching the air and calling defender William to fight.
The match referee's report said he sent D'Alessandro off for kicking Corinthians' Cristian while he was on the ground waiting for medical attention. The Argentine was handed a one-match ban for that incident.
Corinthians midfielder Elias and Inter full back Kleber, who were involved in the second-half fracas, were also suspended for one match.
Coaches Mano Menzes of Corinthians and Inter's Tite, who had both been banished from their benches for coming onto the pitch during the fracas, were cleared by the tribunal.
