This oven hood was vented into the attic by another contractor. This was probably not done properly due to needing a roofer to vent it to the outside. This could cause a fire with trapped grease and cooking odors going up into the attic insulation. Also, this would allow hot humid air from boiling water, cooking etc to hit the cold roof in the winter time and could create mold.
When you have Comfenergy out for our free evaluation, they will look for vents from ovens and bathrooms to make sure they are fully directed to the outside.