An article relating to this blog post on Finextra:
Irish cards blocked after data theft
Hundreds of Irish bank account holders have had their cards cancelled after fraud monitoring systems detected suspicious transactions paid to a US-based e-commerce merchant.
See article
Well, the intention is good but these card numbers need not necessarily have to be stolen to be used.
The luhn-digit algorithm check is easy enough to use to be able to come up with valid card numbers. Most carders actually have a list of at least the first 4 digits of each Issuing Bank. Most times, they even have the range of card numbers of high-end accounts
(platinum, gold, etc.).
I can very well see a ton of cards getting reissued each time carders generate these numbers and validate them in the net and detection systems such as what was used detect the suspicious transactions.
Were they blocked fast enough that these carders/skimmers weren't able to use the clones or validated card numbers? Perfect solution is to allow cardholders to block/unblock their own cards. Unblock them prior to an internet transaction, atm transaction,
foreign-use and block them after. This solution will retire carders and skimmers and it will also save money in reissuing cards.