The nightmare begins early in the morning with an innocuous-looking email on your mobile phone instructing you to check a specific Web site for information about repairing your credit score.

You go to the Web site, decide it’s just another piece of spam, and move on through your normal daily routine. There’s the check-by-phone payment of your credit card bill, a high-level confidential business teleconference discussing sensitive company information, and finally arranging a dinner with that cute co-worker you don’t want your boyfriend to know about. Little do you know that all the while, someone else has been watching–and listening.