Earlier this week Sauber shocked many, including their drivers, when it was announced that Kaltenborn had left the team with immediate effect.
Sauber cited a difference of opinion regarding the future of the team as the reason.
It was initially speculated that former F1 team boss Colin Kolles could replace her, however, Motorsport.com is now reporting that Vasseur is in fact the favourite candidate.
Vasseur was in charge at Renault last season but left the team after clashing with managing director Cyril Abiteboul.
The publication claims the ART boss was seen at Sauber’s Hinwill base on Thursday, giving credence to the rumours.