United Airlines has suspended some customers’ MileagePlus accounts after an unauthorized individual was able to start accessing accounts using login credentials acquired from an unnamed third party breach.
The unauthorized access began on December 9, according to a copy of the notification message to those affected.
The user profiles for MileagePlus accounts include MileagePlus number, account balance, and Premier status. In some cases, it may also include mailing address. If a credit card is on file, all but the last four digits are masked.
Those affected were asked to call the MileagePlus Service Center.