If you total the credit card numbers for any particular card the answer would be the same. For example: totaling the visa credit card number might be 32. The ha

If you total the credit card numbers for any particular card the answer would be the same. For example: totaling the visa credit card number might be 32. The hackers would have to guess the 3 set of numbers if they get the fourth set. So my guess is they would try out different combination with the available expiry date/cvv number