You are correct. There are many rituals to control someone. The most common curse with magic to control someone’s mind is a confusion hex, when you start hearing voices you know your in trouble.
The voices will try and influence the target to cause harm and destroy there life and any happiness. They can also effect the targets subconscious and take control of the active mind to make mistakes, anger flashes and past memories are an influence to cause harm to others even thoughts of murder.
Full possession is rare and usually occurs over a series of years with a death hex where a demon completely takes over the targets mind and destroys there life.
Many mind control hexes with constant voices and blasting noise are created not only for revenge but to achieve a goal to force the target to honor an agreement. Many who have been cheated want to regain what they have lost and have turned to magic to effect a remedy and justice.
Exorcisms are not effective with full possession, however they have shown some success with lesser castings of demonic torment.
This type of black magic requires a lot of experience to control a target using either chaos magic or a patron deity who will accede with ceremonial magic, usually with a pact made. Others may digress this is from my personal experience and perspective.
The Bible and Judas? The Bible is myth and legend combined with parable to influence people. Judas was not possessed but an impoverished individual that was jealous and enriched himself by eliminating a rival rabbi who he secretly hated.