"It appears that, instead of using random SMS codes, Virgin Mobile's codes were sequential so simply changing the last character allowed access to a new set of personal details.

For example, someone who received the code "00XM7Z" could view another customer's details by entering "00XM7Y" or "00XM7X", etc."

Article Link http://www.smh.com.au/news/security/virgin-exposes-customers-details...