3 billion accounts hacked at internet company


Described as the biggest known breach of a company’s computer network...

The company initially disclosed the event in 2016 stating that the 2013 attack on its network had affected one billion accounts. In October 2017, Yahoo's new owner Verizon discovered that 3 billion, not 1 billion, accounts had been compromised.

The unidentified 2013 hackers (said to be unconnected to those behind the company's 2014 hack) exfiltrated names, dates of birth, email addresses, security questions and answers and poorly protected passwords.

In March 2018 it was reported that the company agreed to pay $80 million to settle a federal securities class action lawsuit following the massive data breaches. The settlement included all those who purchased Yahoo securities on the open market between April 2013 and Dec 2016.

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Courtenay Brammar

Experienced global enterprise risk and governance professional. Previously Vice President at Morgan Stanley, Deloitte Risk Advisory practitioner and PRMIA steering committee member in both London and New York.

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  • Altaba Inc.
  • Yahoo Inc.

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