Transfer is possible only between cards issued by Ukrainian banks.
The CVV / CVC is used to help validate that a genuine card is being used during a transaction. The credit card company uses those codes to verify that the person making this purchase actually has the payment card in their possession. It is required for online transactions starting on January 1st, 2003.
With a Visa or Mastercard the CVV/CVC is a three-digit security code printed on the back side of the card.