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I am trying to understand a concept of CPA and CCA attack and I cannot get one thing from the definition. 

If say an an attacker can execute a CPA attack for something like "Send 100 dollars to attacker"Send 100 dollars to attacker that will mean he will get a valid encryption for this message. Now in the definition of the CCA attack is that the adversary should send ANOTHER ciphertext not equal to just obtained one. So the question is: what

What prevents an attacker from just sending the received ciphertext to the recepientrecipient who will think that this is the legitimate message? Or in other words why in the definition attacker is only allowed to send another messages.

I am trying to understand a concept of CPA and CCA attack and I cannot get one thing from the definition. If say an attacker can execute a CPA attack for something like "Send 100 dollars to attacker" that will mean he will get a valid encryption for this message. Now in the definition of the CCA attack is that the adversary should send ANOTHER ciphertext not equal to just obtained one. So the question is: what prevents an attacker from just sending the received ciphertext to the recepient who will think that this is the legitimate message? Or in other words why in the definition attacker is only allowed to send another messages.

I am trying to understand a concept of CPA and CCA attack and I cannot get one thing from the definition. 

If an attacker can execute a CPA attack for something like Send 100 dollars to attacker that will mean he will get a valid encryption for this message. Now in the definition of the CCA attack is that the adversary should send ANOTHER ciphertext not equal to just obtained one.

What prevents an attacker from just sending the received ciphertext to the recipient who will think that this is the legitimate message? Or in other words why in the definition attacker is only allowed to send another messages.

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Chosen plain text and chose ciphertext definitions clarification

I am trying to understand a concept of CPA and CCA attack and I cannot get one thing from the definition. If say an attacker can execute a CPA attack for something like "Send 100 dollars to attacker" that will mean he will get a valid encryption for this message. Now in the definition of the CCA attack is that the adversary should send ANOTHER ciphertext not equal to just obtained one. So the question is: what prevents an attacker from just sending the received ciphertext to the recepient who will think that this is the legitimate message? Or in other words why in the definition attacker is only allowed to send another messages.