Watch CBS News

Yahoo: Hackers Stole Data From Over 1 Billion User Accounts

PHILADELPHIA (CBS/AP) -- Yahoo reveals that over 1 billion user accounts were hacked.

Yahoo said in a press release that hackers stole data associated with more than 1 billion accounts in August 2013. The Sunnyvale, California, company was also home to what's now most likely the second largest hack in history, one that exposed 500 million Yahoo accounts . The company disclosed that breach in September. Yahoo said it hasn't identified the intrusion associated with this theft.

"Yahoo believes this incident is likely distinct from the incident the company disclosed on September 22, 2016," the statement reads.

Yahoo said the stolen user account information may have included names, email addresses, telephone numbers, dates of birth, hashed passwords and encrypted or unencrypted security questions and answers.

However, the stolen information did not include passwords in clear text, payment card data or users' bank account information.

Yahoo is notifying potentially affected users. The company is taking steps to secure the accounts, including requiring users to change their passwords.

"Separately, Yahoo previously disclosed that its outside forensic experts were investigating the creation of forged cookies that could allow an intruder to access users' accounts without a password. Based on the ongoing investigation, the company believes an unauthorized third party accessed the company's proprietary code to learn how to forge cookies," the statement reads. "The outside forensic experts have identified user accounts for which they believe forged cookies were taken or used. Yahoo is notifying the affected account holders, and has invalidated the forged cookies. The company has connected some of this activity to the same state-sponsored actor believed to be responsible for the data theft the company disclosed on September 22, 2016."

Yahoo is also warning users from downloading attachments from suspicious emails.

The new hack revelation raises fresh questions about Verizon's $4.8 billion proposed acquisition of Yahoo, and whether the big mobile carrier will seek to modify or abandon its bid. If the hacks cause a user backlash against Yahoo, the company's services wouldn't be as valuable to Verizon. The telecom giant wants Yahoo and its many users to help it build a digital ad business.

In a statement, Verizon said that it will evaluate the situation as Yahoo investigates and will review the "new development before reaching any final conclusions." Spokesman Bob Varettoni declined to answer further questions.

Yahoo said Wednesday that it is requiring users to change their passwords and invalidating security questions so they can't be used to hack into accounts.

(TM and © Copyright 2016 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2016 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

View CBS News In
CBS News App Open
Chrome Safari Continue
Be the first to know
Get browser notifications for breaking news, live events, and exclusive reporting.