Updated from 5:39 p.m. with additional details.
Another billion Yahoo! (YHOO) accounts have been hacked, the company announced Wednesday after the market closed. The new breach is on top of the 500 million hacked accounts that were previously disclosed, and Yahoo! said it believes the two attacks were not related.
The news comes as Yahoo! works to close its $4.8 billion sale to Verizon (VZ) . When the companies announced the sale in July, Yahoo! put its total monthly average users at more than 1 billion, with 600 million mobile accounts.
Yahoo! shares were down nearly 2.5% to $39.89 in after-hours trading on Wednesday. During the day, shares fell 1.4%.
"Based on further analysis of this data by the forensic experts, Yahoo! believes an unauthorized third party, in August 2013, stole data associated with more than one billion user accounts," Yahoo! said in a statement. "The company has not been able to identify the intrusion associated with this theft. Yahoo! believes this incident is likely distinct from the incident the company disclosed on September 22, 2016."
The data thieves may have gotten away with names, email addresses, telephone numbers, dates of birth, obscured passwords and security questions and answers. The investigation indicates that information from bank accounts, payment cards and passwords in clear text were not part of the breach, Yahoo said.
Verizon said it would continue to watch Yahoo's review of the hacks. "As we've said all along, we will evaluate the situation as Yahoo continues its investigation," the telecom said. "We will review the impact of this new development before reaching any final conclusions." Verizon was previously reported to be trying to get a billion dollars knocked off its purchase price because of the earlier intrusions.
Before the latest hacks, Verizon CEO Lowell McAdam said at a Dec. 6 New York investor conference that the telecom still hopes to close the purchase of Yahoo!
"They've been doing all their work on the breach," McAdam said. "This is one of those things that we need to give them lots of time to do a full analysis before we move forward with that, and that's the process we're in at this point."
