Is croissant a contraband?

Yes

According to the inquiry of Amber Law Network, claw knives belong to controlled knives and are contraband. Controlled knives are controlled instruments stipulated by the state, and their sales, production and supply should be specially managed by public security organs. There is a designated point of sale, and no other merchant may sell it to other units or individuals by himself. At the same time, it is illegal for any citizen to buy or use it without permission.