AT&T is apologizing for an incident in which one of its workers improperly accessed account information for a limited number of customers.
"We take our customers' privacy very seriously and value the trust they have in us," AT&T spokesman Mark Siegel said in a statement to Re/code. "Unfortunately we recently learned that one of our employees did not follow our strict privacy rules and inappropriately obtained personal information for a limited number of customers."
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Siegel said AT&T is directly contacting affected customers. The company is in contact with law enforcement and said any unauthorized charges will be reversed.
In a sample letter posted to the Vermont Attorney General's website, AT&T said the personal information included Social Security numbers and other account data.
"On behalf of AT&T, please accept my sincere apology for this incident," AT&T's Michael Chiaramonte said in the letter. "Simply put, this is not the way we conduct business and, as a result, this individual no longer works for AT&T."
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The incident is different from some of the larger breaches out there in which outsiders gained access to customer data en masse, such as recent issues with Target, Home Depot and JPMorgan Chase.
AT&T is offering one year of credit monitoring to affected customers, according to the letter.
The breach was earlier reported by Threatpost.
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