Is the subcontractor sinful if a task is assigned to him, knowing that there is corruption in its approval, and he receives a wage for performing the executive duties of that task?

It is not permissible to accept internal works that involve corruption, fraud, and squandering of public funds, because this constitutes participation and assistance in sin and aggression, in accordance with the Almighty's saying: "And do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty." Likewise, it is not permissible to deal with usurped money or money taken unlawfully for whoever knows about it.