Slashdot reports how to find large numbers of credit cards with user information using a simple Google search. A long and interesting discussion after the posting provides suggestions on why credit card companies don’t put a stop to this.

Take the first 8 digits of a standard 16-digit credit card number. Search for them on Google in "nnnn nnnn" form. Since the 8-digit prefix of a given card number is often shared with many other cards, about 1/4 of credit card numbers in my random test, turned up pages that included other credit card numbers, and about 1 in 10 turned up a "treasure trove" of card numbers that were exposed through someone's sloppily written Web app. If the numbers were displayed along with people's names and phone numbers, sometimes I would call the users to tell them that I'd found their cards on the Internet, and many of them said that the cards were still active and that this was the first they'd heard that the numbers had been compromised.

Slashdot | Why Are CC Numbers Still So Easy To Find?