17 Biggest Data Breaches of All Time

Page 15 of 18

4. Yahoo

No. of records: 500 million
Year: 2014

What is believed to be a Chinese State-sponsored hack targeted Yahoo and its massive database in 2014, affecting some 500 million users, with the leaked data including names, email addresses, phone numbers, birth dates, encrypted passwords, and security questions and answers. The breach was announced in November 2016, but a following security filing revealed the company’s information security team and senior execs knew of the situation after it happened, though they didn’t properly comprehend what had happened so their response to the situation was poor.

Yahoo! Inc. (NASDAQ:YHOO), Sign, Logo, World Headquarters, Symbol, 701 first avenue,

Katherine Welles / Shutterstock.com

Page 15 of 18