Is it permissible to advise people to distance themselves from someone known for their bad behavior and open commission of major sins like drinking alcohol?

Warning against the actions of the wicked and those who commit major sins is obligatory. It is incumbent upon a Muslim to advise his brethren and expose the states of the wicked, out of fear of falling into their traps, and to offer them sincere counsel, hoping that Allah may guide them; for the Prophet, peace and blessings be upon him, said: "Religion is sincere advice."