Video from Sunday's season-ending Brazilian Grand Prix appears to show that Vettel passed a Toro Rosso car while there was a yellow caution light lit. If a rules breach is proven, Vettel could be hit with a 20-second penalty, which would move him from sixth to eighth place in the race and give Ferrari driver Fernando Alonso the F1 title by one point.
"We're looking at the video. We have until tomorrow to file an appeal," Ferrari spokesman Luca Colajanni told The Associated Press on Thursday.
One of the videos was taken from a camera lodged on Vettel's Red Bull car.
Alonso finished second in the race but Vettel won the title by three points.
Vettel appeared to be in big trouble when he was bumped shortly after the start of the race and spun. He dropped to last place before he could turn his car around and begin a difficult pursuit. But he steadily worked his way up the field despite a slightly damaged car and no radio communication.
It was during Vettel's climb back through the field that the alleged illegal overtake of the Toro Rosso car occurred.
With the title, the 25-year-old Vettel became F1's youngest three-time champion.
If Alonso gets the title, he'll become a three-time champion.
Ferrari has until Friday to lodge an appeal.