HanesBrands Security Data Breach of customers personal information and last four digits of credit card Winston-Salem North Carolina

Just received an email from Hanes-Brands saying my personal information and the last four numbers  of my credit card had been stolen in a security breach. I called them and was told not to worry because the rest of the credit card number as encrypted.

I was also told  Hanes will NOT make this breach public, and the emails sent out said don't email back.

I think this is a very cavalier response to  security breach. My credit card company told me one if the last four numbers are stolen, thieves then begin working backwards on all possible combinations, and sooner or later end up with the full number.

I would like some advice on how to get a responsible response out of Hanes.