Chosen Ciphertext Attack

Requirements

 * A decryption service

Regular Attack
In this attack, the attacker has access to a decryption service and mounts a successful attack if they are able to get information about a "target ciphertext" that is provided later. However, the decryption service stops working when the "target ciphertext" is provided to the attacker

Adaptive Chosen Ciphertext Attack
In this more advanced attack, the attacker does not lose the ability to use the decryption service after the "target ciphertext" is given. However, the attacker still cannot use the decryption service on the "target ciphertext"