By Fiona Leishman AT&T users have been hit by a ‘dark web leak’, with millions of Social Security numbers being released. AT&T is now alerting millions of customers that their personal details have been leaked in a “dark web” breach, which includes Social Security numbers. The company confirmed on Saturday that a dataset found on the “dark web” has information including Social Security numbers for about 7.6 million current AT&T account holders and 65.4 million former account holders. The firm has already reset the passcodes of current users. AT&T said it will be contacting account holders whos…