Groupon Exposes Customer Emails In Google Results

Savvy Internet surfer Chris Crompton has found a flaw in Groupon's email link encryption where adding the search term "addx" (exact Google search = allinurl: addx site:groupon.com) brings up emails of people who have subscribed to the Groupon newsletter. I am unable to tell whether these emails are from people who actually purchased the deals or just signed up for Groupon's massive email list. It looks like this is some kind of Google Analytics tracking flaw for a Groupon marketing campaign, and the emails are from people who have referred deals to others through Groupon's insecure links.

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