The veteran MotoGP star was penalized by stewards after being blamed for a clash with Marc Marquez at the Malaysian Grand Prix and punished for dangerous riding.
"Mr. Rossi has filed an urgent application to stay the execution of the challenged decision in order not to lose his place on the starting grid at the next, and last, event of the season," CAS said in a statement
"Mr. Rossi seeks annulment or reduction of the penalty."
The 36-year-old holds a slim seven-point advantage over Movistar Yamaha teammate Jorge Lorenzo ahead of the finale in Valencia on November 8. CAS will make a ruling by November 6.
Rossi can become world champion for the 10th time even if Lorenzo wins the race -- but he would have to finish second in order to do so.
He was sanctioned by Race Direction
after appearing to kick out at Marquez, who subsequently lost control and crashed out of the race at the Sepang International Circuit.
Rossi insisted his foot came off his foot peg as a result of contact with Marquez, who won the world title in 2013-14 but is out of contention in third place this year.
The punishment sparked a campaign to force Race Direction to reverse its decision to punish Rossi.
By Friday, 544,000 people had signed a petition entitled "Remove the penalty from Valentino Rossi and bring back integrity to the Championship," logged on change.org
by British fan Nicholas Davis.
The petition -- which has been translated into 20 languages -- demonstrates the strength of feeling from fans who feel their favorite has been unfairly treated.
As well as accusing MotoGP administrators of wrongly punishing Rossi, it hits out at them for failing to sanction Lorenzo for overtaking on a yellow flag -- an infringement that could have harmed the Spaniard's prospects of winning a third title if officials had seen it.
"You have just condoned dirty racing tactics by punishing Valentino Rossi for pursuing the championship whilst being harassed and sabotaged by Marc Marquez," the petition reads. "At the same time, you have allowed Jorge Lorenzo to overtake on a yellow flag without penalty."
"Justifying your decision by stating that there is no rule to deal with the actions of Marc Marquez is as absurd as saying there is no rule to prevent riders shooting at other riders with guns.
"Would you allow that because it didn't break an existing rule?"
Motorcycling's ruling body, FIM, said on the MotoGP website Friday that it would not comment on Rossi's appeal.
However, on Thursday the website published an open letter from FIM president Vito Ippolito
, who said the fallout has "had a damaging effect on the staging of our competitions and poisoned the atmosphere around the sport."
"Riders, teams, manufacturers and sponsors should not only respect the rules but they should accept the decisions of the officials, whatever they may be," Ippolito said.
"Otherwise, they are contributing to anarchy and undermining the future development of our sport."
Speaking in the aftermath of the Malaysia race, Movistar Yamaha managing director Lin Jarvis said he was "not defending" Rossi's actions.
"This is why he received the penalty as it was judged that this was not a move within the rules of racing," he added.
"I think that what happened... was the result of at least a couple of races of fierce competition between Marc Marquez and Valentino Rossi."
Meanwhile, an angry Lorenzo said he believed Rossi should have been docked championship points, adding: "Yes, he starts last (in Valencia) -- but it's not fair. We have to respect the decision, but I don't share it."