All 3 B Yahoo accounts hacked in 2013

BOSTON (AP) — Yahoo has tripled down on what was already the largest data breach in history, saying it affected all three billion accounts on its service, not the one billion it revealed late last year.

The company announced Tuesday that it has sent emails providing notice to additional user accounts affected by the August 2013 data theft.

The breach now affects a number that represents nearly “half the world,” said Sam Curry, chief security officer for Boston-based firm Cybereason, though there’s likely to be more accounts than actual users.

“Whether it’s one billion or three billion is largely immaterial. Assume it affects you,” Curry said. “Privacy is really the victim here.”

Yahoo first disclosed the breach in December. The stolen information included names, e-mail addresses, phone numbers, birthdates and security questions and answers.

Following its acquisition by Verizon in June, Yahoo says it obtained new intelligence while investigating the breach with help from outside forensic experts. It says the stolen customer information did not include passwords in clear text, payment card data or bank account information.

Yahoo had already required users to change their passwords so they couldn’t be used to hack into accounts.