Gennaro Gattuso's side did not travel to Turin for the game on 4 October after players Piotr Zielinski and Eljif Elmas, as well as staff member Giandomenico Costi, tested positive for coronavirus.
Lega Serie A refused a request from Napoli, which argued it had been banned from travelling by local health authorities, to postpone the meeting at the Allianz Stadium because it technically still had at least 13 players available for selection.
Juve had already confirmed its intention to play despite reporting two positive cases among staff on the day prior to the match.
Andrea Pirlo named a starting XI but the team did not warm-up and the game failed to go ahead as scheduled.
Lega Serie A's disciplinary commission deemed that Napoli did not have sufficient reason to miss the fixture, although Napoli are expected to lodge an appeal against the sanctions.