OWINGS MILLS, Md.—CareFirst, a major provider of Blue Cross Blue Shield insurance, has disclosed that its computers have been breached and that as many as 1.1 million customer data records may be at risk.
It has become the third major insurer in the U.S. to announce such a breach in 2015, although in its case it said the breach occurred in June 2014.
CareFirst said, however, that while hackers obtained customer names, e-mails and birthdates, it is believed they did not obtain personal financial or medical information.
The company said it has been under “constant attack” by hackers.