The credit card has a low security system and enables countless opportunities for fraud. This opportunity has created a huge black market for stolen card numbers where they are used quickly before the stolen number gets reported. Despite the fact that the card issuing company’s effort to improve the security of the card for online purchasing using the credit card.
The problem lies with the merchant who has a poor implementation of security when dealing with the card number of their client. For an example if the merchant has implement encryption to hide the card number such as SSL the card number will be sent to someone to process the card details manually at the card terminal. When this happens the card number became readable to humans this is a security risk. It may lead to the card number to be leaked and be misused by others.
However now many card issuing company are offering system such as ClearCommence where the encrypted card detail of the user is captured directly from the merchant’s website and send directly to the payment processor. This greatly decreases the chance of the card number being leak out to the public.
Reference:
http://en.wikipedia.org/wiki/Credit_card