Yahoo now says all of its user accounts were affected by August 2013 data breach

Company previously stated one-third of accounts affected by breach

1995: Yahoo! is incorporated.
1995: Yahoo! is incorporated. (Justin Sullivan/Getty Images)

DETROIT – Yahoo, now part of Oath, announced Tuesday that a 2013 data breach affected more accounts than previously stated.

In December 2016, the company stated approximately one billion out of three billion accounts were affected by a data breach.

Today, the company says all of their accounts were affected - all three billion. Here's more info from Verizon, Yahoo/Oath's parent company:

Yahoo took action to protect all accounts, including directly notifying impacted users identified at the time, requiring password changes and invalidating unencrypted security questions and answers so that they could not be used to access an account. Yahoo also notified users via a notice on its website.

Subsequent to Yahoo's acquisition by Verizon, and during integration, the company recently obtained new intelligence and now believes, following an investigation with the assistance of outside forensic experts, that all Yahoo user accounts were affected by the August 2013 theft. While this is not a new security issue, Yahoo is sending email notifications to the additional affected user accounts. The investigation indicates that the user account information that was stolen did not include passwords in clear text, payment card data, or bank account information. The company is continuing to work closely with law enforcement.

"Verizon is committed to the highest standards of accountability and transparency, and we proactively work to ensure the safety and security of our users and networks in an evolving landscape of online threats," said Chandra McMahon, Chief Information Security Officer, Verizon. "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."

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