Predictable serial number attack

A predictable serial number attack is a form of security exploit in which the algorithm for generating serial numbers for a particular purpose is guessed, discovered, or reverse engineered, a new serial number is predicted using the algorithm, and the newly generated serial number is then used for a fraudulent purpose, either to obtain an undeserved benefit or to deny service to the legitimate holder of the serial number. == Example == Suppose there is a phone card available for sale that offers telephone service by entering the serial number printed on the card.

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