The blog posting lists the personal information that Sony believes has been taken.
* Name
* Address (city, state/province, zip or postal code)
* Country
* E-mail address
* Date of birth
* PlayStation Network/Qriocity passwords and login
* Handle/PSN online ID
Mr Caplin added: "It is also possible that your profile data, including purchase history and billing address (city, state, zip), and your PlayStation Network/Qriocity password security answers may have been obtained".
Credit cards
Sony admitted that credit card information, used to purchase games, films and music, may also have been stolen.
"While there is no evidence that credit card data was taken at this time, we cannot rule out the possibility," Mr Caplin said.
"If you have provided your credit card data through PlayStation Network or Qriocity, to be on the safe side we are advising you that your credit card number (excluding security code) and expiration date may also have been obtained."