Zuber, who started second on the grid, got the jump on pole sitter Tristan Gommendy at the start and was never headed, pulling out a 5.547 second advantage over Kubica at the chequered flag.
The Austrian has come close to winning in the series when dominating Valencia's feature race before a strategy decision robbed him of nearly a 12-second lead.
"Everything went perfectly today," Zuber said. "From the middle of the race it was quite easy. I just had to hold on."
Epsilon Euskadi driver Kubica secured the title with the runner-up slot after his closest rival Adrian Valles retired from the race, pulling into the pits with mechanical difficulties. Kubica braved it out to beat Gommendy into second through the first couple of corners, and because he finished ahead of him and the other theoretical title contender Markus Winkelhock, the Polish driver secured the title three races early.
"I thought I'd have to fight for the championship until the last round at Monza," Kubica said. "It is really good for me to take it this early considering that there were seven different winners in the first seven races. It shows that I am quick and consistent."
Gommendy finished third after being unable to live with Kubica after the first lap. Markus Winkelhock finished fourth, ahead of Kubica's teammate Felix Porteiro.
CLASSIFIED: Pos Driver Team Time 1. Zuber Carlin Motorsport 28:03.213 2. Kubica Epsilon Euskadi + 5.647 3. Gommendy KTR + 8.097 4. Winkelhock Draco Multiracing USA + 9.042 5. Porteiro Epsilon Euskadi + 11.677 6. Fleming Jenzer Motorsport + 13.437 7. Pilet GD Racing + 19.397 8. Montanari Draco Multiracing USA + 21.689 9. Pagenaud DHG Saulnier Racing + 22.267 10. Power Carlin Motorsport + 23.046 11. Pavlovic GD Racing + 35.619 12. Maldonado Dams + 45.940 13. Pellegrino RC Motorsport + 46.999 14. Fukuda DHG Saulnier Racing + 49.185 15. Carbone Eurointernational + 49.806 16. Rigon Victory Engineering + 50.391 17. Hanley Cram Competition + 51.671 18. Miguez Pons Racing + 55.880 19. Van Lagen KTR + 56.006 20. Meneghello Eurointernational +1:02.213 21. Bellarosa Avelon Formula +1:10.359 22. Prost Dams +1:11.132 23. Bennani Avelon Formula + 1 lap 24. Sharp Jenzer Motorsport + 2 laps NOT CLASSIFIED/RETIREMENTS: Driver Team On Lap Tedeschi RC Motorsport 15 Valles Pons Racing 12 Rees Interwetten 7 Pasini Cram Competition 3 Fastest Lap: Zuber, 1:27.450
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