According to a letter posted on the website of the Attorney General of Vermont on Oct. 1, the company said the person may have obtained Social Security numbers, driver's license numbers and AT&T services customers subscribed to.
Federal authorities have been notified regarding the incident, and the employee has since been fired, the carrier said.
"Unfortunately, we recently learned that one of our employees did not follow our strict privacy rules and inappropriately obtained some customer information. This individual no longer works at AT&T and we are directly contacting the limited number of affected customers," an AT&T spokesman said.
The news follows breaches that include a massive cyber-attack at JPMorgan Chase & Co, a theft involving Apple Inc's iCloud and an alleged international computer hacking ring charged with stealing more than $100 million worth of software and data - some of it used to train military pilots and some related to Microsoft Corp's Xbox.
(Also see: Hackers Charged for Stealing Data and Software From US Army, Xbox)
© Thomson Reuters 2014
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