police found more than six thousand letters in his home and car.
There are cheap dates and there are cheap bribes. Seven clerks who worked in the New York offices of the Social Security Administration were willing to accept between ten dollars and seventy-five dollars to reveal a person's birth date and mother's maiden name to a group of Nigerians, ones apparently taking time off from sending out letter scams. The Nigerians needed the information to activate new credit cards they had intercepted before they got to their rightful owners. A common security feature credit card issuers use is the requirement that a cardholder receiving a new card must call a toll-free number and give his mother's maiden name, date of birth, and other information. Over a relatively short period of time, the Nigerian ring rounded up a breathtaking twenty thousand cards and charged more than $10 million on them.
But it's not even necessary to steal credit card information. That's usually for the amateur crook. A true criminal knows exactly where to go to get it, and that's from what we call a credit card generator. There are maybe a dozen or so websites around the world that are maintained for criminals by other criminals, a nice little service in the intricate fraud network. If you know the code to get into the website, you can get any information that you want. The people who maintain the sites generally charge someone five thousand dollars to ten thousand dollars for regular use. It may sound like a lot, but it's a bargain considering what you get for your investment.
Once you get onto the home page of the site, you enter a code. That takes you to the next screen. You're asked what information you want. Do you want an American Express card number, Diner's Club, Discover Card? Maybe you just want a utility company account number? Whatever you click on brings you to the next page. Say you check Visa. Then you're invited to select an institution: Citibank, Bank of America, Household Bank. You click on one, and within twenty seconds you get the names, numbers, and expiration dates of valid cards. Number after number after number. Each of these generators contains thousands of card numbers. I've checked them out, and I've never logged on and not gotten a valid card.
There are also software programs that will essentially pluck valid credit card numbers out of the air. Legitimate card numbers generally end with what's called a "check digit." It's a number added for the purpose of validating the authenticity of the card number. This check digit is derived from the card's other numbers by what is known as a Luhn formula or Mod-10 algorithm. I'm not going to get into higher math, but suffice to say, a quick way to verify a card number is to run the algorithm and compare the check digit you get with the check digit encoded with the credit card number. As it happens, the Mod-10 algorithm is fairly widely known and assorted computer programs use it to churn out numbers likely to fool authorization checks.
Now, these don't always prove useful, as the issuing bank will normally confirm the number, expiration, and mailing address when you make an Internet purchase, thus thwarting any software-generated account number. But for inexpensive purchases, generally those under twenty dollars, and often higher amounts overseas, banks commonly run a "stand-in" check, a quick authorization that does nothing more than see that the account number is valid against the "check digit." Consequently, thieves armed with these computer-generated numbers will log onto online merchant sites and type in number after number until they find one that gets taken, and then they make a blizzard of small purchases.
In so many ways, the Internet has opened up a wide new avenue for crooks to get hold of your card number and use it for nefarious purposes. I'll discuss this and other computer crimes in further detail in a later chapter on the Internet.
MING'S BOOSTER RING
Account boosting is yet another popular trick of credit card thieves. This is a scheme where criminals acquire legitimate credit cards and accrue balances on them. The criminal then sends the issuer a payment by overnight delivery using a stolen or counterfeit check. The payment exceeds the balance, and thus "boosts" the account's credit line. Under Federal law, banks have to post card payments before the checks clear and so they have no choice but to credit your account. The next day,