"In detailing the reasons for their verdict ... UEFA said Ribery was guilty of assault," the Bundesliga club said on their website.
"FC Bayern cannot accept this verdict in any sense and holds that it is entirely false. The accusation of assault is inapplicable in this case," the club added.
"Ribery cannot be accused of intentionally attempting to injure his opponent ... Lisandro Lopez was able to continue the match uninjured. FC Bayern and Franck Ribery cannot accept the verdict and will lodge an appeal, using all legal remedies at the club's disposal."
The influential Ribery was sent off for a bad tackle on Olympique Lyon striker Lopez in the first half of last week's semi-final first leg.
The red card meant he was automatically suspended for the second leg in France on Tuesday, which Bayern won 3-0 to advance 4-0 on aggregate, and European football's governing body UEFA then decided to add two further games to his punishment.
The Champions League final, to be held at Real Madrid's Santiago Bernabeu stadium on May 22, will be against Inter Milan or Barcelona.
SIGNIFICANT BLOW
Ribery's absence, if confirmed, would be a significant blow to Bayern who have reached the final for the first time since they won the competition in 2001.
The Frenchman joined the club in 2007 and made an immediate impact, helping the Bavarians win a league and cup double in his first season.
The 27-year-old, though, has yet to decide whether he will stay at Bayern at the end of the campaign.
Ribery's sending-off against Lyon came after it emerged he had been quizzed by French police as a witness in a prostitution investigation.
Bayern coach Louis van Gaal said at the time he felt Ribery's tackle was a yellow card offence.
"I thought, watching from the bench, he stood too long on the opponent's leg," Van Gaal said. "I do not think it was a red card because it was the inner foot and not a foul with full force."
Bayern are still chasing a Bundesliga, German Cup and Champions League treble.
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