AT&T informs users of data breach and resets millions of passcodes

AT&T said it has begun notifying millions of customers about the theft of personal data recently discovered online.

The telecommunications giant said Saturday that a dataset found on the "dark web" contains information such as Social Security numbers for about 7.6 million current AT&T account holders and 65.4 million former account holders.

The company said it has already reset the passcodes of current users and will be communicating with account holders whose sensitive personal information was compromised.