A Giant/Shell gas promotion ties access users’ rewards points to their phone numbers, opening up a gaping security breach for unscrupulous users who want to swipe points from others.

Mike from Clever Dude says the promotion lets you access your points by typing in your phone number at the gas pump. If others know that you use the promotion, or just want to take a wild guess, they can get ahold of your points and drain your discounted gas down their tanks.

Mike recommends avoiding this potential exploit by registering your account under a Google Voice number you keep to yourself.

How you can cheat on Giant’s Gas Promo…and steal from others! [Clever Dude]

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