Oath did not specify what information was at risk for the users, but said that hackers did not steal passwords, credit card numbers or bank account information.
Yahoo on Tuesday announced that its massive data breach revealed last year affected all of its three billion accounts.
This is triple the number the company had said were impacted when it revealed the breach last year.
After Yahoo was purchased by Verizon this year, it was rebranded as Oath, which announced that it would be notifying all of the additional users impacted by the breach.
"Our investment in Yahoo is allowing that team to continue to take significant steps to enhance their security, as well as benefit from Verizon's experience and resources," said Chandra McMahon, Verizon's head of information security, as quoted by The Hill.
Oath did not specify what information was at risk for the users, but said that hackers did not steal passwords, credit card numbers or bank account information. It also extended complete cooperation with law enforcement in its investigation of the breach.
On that note, when Yahoo first announced the breach in December 2016, it said that names, emails, addresses, dates of birth and phone numbers were among the stolen information.
Image: A Yahoo logo is pictured in front of a building in Rolle, 30 km east of Geneva. Photograph: Denis Balibouse/File photo/Reuters.