Is the salary derived from the profits of loans given to poor families lawful or unlawful?

It is not permissible to work in the field of usurious lending, because every stipulated increase on a loan is forbidden usury (riba), even if its name is changed. The prohibition of this work is based on the Islamic legal principle that forbids cooperation in sin and aggression, in accordance with His, the Almighty’s, saying: "And do not cooperate in sin and aggression."