The CVV2 is a 3- or 4-digit value printed on the card or signature strip, but not encoded on the magnetic stripe.

MasterCard and Visa credit cards have a 3-digit code, called the "CVC2" (card validation code) and "CVV2" (card verification value). It is not embossed like the card number, and is always the final group of numbers printed on the back signature panel of the card.

Some new MasterCard and Visa cards feature the "CVC2" in a separate panel to the right of the signature strip.[2] This has been done to prevent overwriting of the numbers by signing the card. The number is generated when the card is issued, by hashing the card number and expiration date under a key known only to the issuing bank. Supplying this code in a transaction is intended to verify that the customer has the card in their possession. Knowledge of the code proves that the customer has seen the card, or has seen a record made by somebody who saw the card. To date, no cracks for this system are known.