Clearly that Yahoo's account information for 3 billion people was leaked out

ByEsther Vargas

Finally in June 2017, finallyTakeover negotiations that did not proceed quite wellYahoo got together and acquired by Verizon which is a major telecommunications carrier in the U.S. but in the past cyber attacks of an unprecedented size that user account information of all 3 billion people leaked in the past It became clear that it was received.

Yahoo Provides Notice to Additional Users Affected by Previously Disclosed 2013 Data Theft
https://www.sec.gov/Archives/edgar/data/732712/000073271217000003/a2017_10x3xoathxexhibitx991.htm


Yahoo providing notice to additional users affected by last disclosed 2013 data theft
https://www.oath.com/press/yahoo-provides-notice-to-additional-users-affected-by-previously/


Yahoo now thinks all 3B accounts were impacted by 2013 breach, not 1B as thought | TechCrunch
https://techcrunch.com/2017/10/03/yahoo-says-all-3b-accounts-were-impacted-by-2013-breach-not-1b-as-thought/

On December 14, 2016, Yahoo announced that about 1 billion user account information was stolen by the attack received from the hacker in August 2013. The leaked information included the user's telephone number, date of birth, answer to security question, etc. It was reported that the information leak from the company was the largest ever in the past.

Yahoo gets the biggest hacking ever in the history of stolen user account information for 1 billion people - GIGAZINE


Even after being acquired by Verizon, Yahoo continued to investigate the hacking damage in 2013 in cooperation with external experts. As a result, it turned out that all 3 billion users at the time of hacking were affected by information leakage. As a result, in December 2016, we are notified by e-mail even for "Accounts found to be newly victims" that were considered not to be victims. According to the survey, stolen user information includesClear textPassword, credit card payment information, bank account information, etc. were not included.

Verizon Chief Information Security Officer Mr. Chandra McMahon, who acquired Yahoo, said, "Verizon is committed to keeping the highest standards of responsibility and transparency, and in response to evolving online threats We are actively working to ensure the security and security of users and networks.To our investment, Yahoo benefits from Verizon's experience and resources, and you can take an important step to strengthen security I will tell you.