7#  ) IIII SooxI I*sI-IIsIIIIIIWhy cybercrooks love cellular: Dug up by Mister Kray From Forbes Dec. 21, 1992 CELLULAR PHONES provide cybercrooks with golden opportunities for telephone toll fraud, as many shocked cellular customers are discovering. For example, one U S West Cellular customer in Albuquerque recently received a hefty phone bill. Total: $20,000. Customers are not held responsible when their phone numbers are ripped offand misused. But you may be forced to have your cellular phone number changed. The cellular carriers are the big losersto the tune of an estimated $300 million per year in unauthorized calls. How do the crooks get the numbers? There are two common methods: cloning and tumbling. Each cellular phone has two numbersa mobile identification number (MIN) and an electronic serial number (ESN). Every time you make a call, the chip transmits both numbers to the local switching office for verification and billing. Cloning irivolves altering the microchip in another cellular phone so that both the MIN and ESN numbers match those stolen from a bona fide customer. The altering can be done with a personal computer. The MIN and ESN numbers are either purchased from insiders or plucked from the airwaves with a legal device, about the size of a textbook, that can be plugged into a vehicle's cigarette lighter receptacle. Cellular companies are starting to watch for suspicious calling patterns. But the cloning may not be detected until the customer gets his bill. The second methodtumblingalso involves using a personal computer to alter a microchip in a cellular phone so that its numbers change after every phone call. Tumbling doesn't require any signal plucking. It takes advantage of the fact that cellular companies allow "roaming"letting you make calls away from your home area. When you use a cellular phone far from your home base, it may take too long fbr the local switching office to verify your MIN and ESN numbers. So the first call usually goes through while the verification goes on. If the numbers are invalid, no more calls will be permitted by that office on that phone. In 1987 a California hacker figured out how to use his personal computer to reprogram the chip in a cellular phone. Authorities say one of his pals started selling altered chips and chipped-up phones. Other hackers figured out how to make the chips generate new, fake ESN numbers every time the cellular phone was used, thereby short-circuiting the verification process. By 1991 chipped-up, tumbling ESN phones were in use all over the U.S. The cellular carriers hope to scotch the problem of tumbling with instant verification. But that won't stop the clones. How do crooks cash in? Drug dealers buy (for up to $3,200) or lease (about $750 per day) cellular phones with altered chips. So do the "call-sell" crooks, who retail long distance calls to immigrants often for less than phone companies charge. That's why a victim will get bills for calls all over the world, but especially to Colombia, Bolivia and other drugexporting countries. -W.G.F. and B.McM. _ x(MISTRALSNde Demi-Bold45   @   005OPO˕__*4$\p @_p @_p @_p @_p @_p @_5$\p @_p @_p @_p @_p @_p @_5$\p @P_p @P_p @P_4$p\p @P_p @P_p @P_O[f6ɒ[[&4$\p @_p @_p @_p @_p @_p @_6$\p @_p @_p @_p @_p @_p @_6$\p @_p @_p @_p @_p @_p @_6$\p @_p @_p @_p @_p @_p @_6 > qɔ]&6$\p @_p @_p @_p @_p @_6$\p @_p @_p @_p @_p @_4$\p @_p @_p @_p @_p @_6$\p @_p @_p @_p @_p @_p @_ q  ɔ4$\p @_p @_p @_p @_p @_6$\p @_p @_p @_p @_p @_    p O6 q  HH(FG(HH(d'@=/RH -:LaserWriter GenevaTimesOOO,  Mister Kray Mister Kray