Coming on the heels of the recent breach at restaurant chain P.F. Changs, ATT states that a third-party vendor managed to expose personal data for an untold number of customers earlier this year. According to a letter ATT sent to its customers, the breach was caused by a service that unlocks cell phones for its customers. We recently learned that three employees of one of our vendors accessed some ATT customer accounts without proper authorization, said ATT in a statement sent to PhoneScoop. At this point, its unclear how many customers were affected and if their personal data is in any real danger.