• Home
  • News
  • Fortune 500
  • Tech
  • Finance
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Tech

Yahoo: “Forged Cookies” Used to Hack 32 Million Accounts

By
Reuters
Reuters
Down Arrow Button Icon
By
Reuters
Reuters
Down Arrow Button Icon
March 1, 2017, 7:09 PM ET
Yahoo Said to Propose Job Cuts as Part of Mayer's Revival Plan
Yahoo! Inc. company headquarters in Sunnyvale, California, on Jan. 7, 2016. Noah Berger—Bloomberg/Getty Images

Yahoo, which disclosed two massive data breaches last year, said on Wednesday that about 32 million user accounts were accessed by intruders in the last two years using forged cookies.

The company said some of the latest intrusions can be connected to the “same state-sponsored actor believed to be responsible for the 2014 breach,” in which at least 500 million accounts were affected.

“Based on the investigation, we believe an unauthorized third party accessed the company’s proprietary code to learn how to forge certain cookies,” Yahoo said in its latest annual filing.

Get Data Sheet, Fortune’s technology newsletter.

These cookies have been invalidated so they cannot be used to access user accounts, the company said.

Forged cookies allow an intruder to access a user’s account without a password.

Yahoo also said in December that data from more than 1 billion user accounts was compromised in August 2013, making it the largest breach in history.

Yahoo’s CEO Resigns from Company Board

The company said on Wednesday that it would not award CEO Marissa Mayer a cash bonus for 2016, following the independent committee’s findings related to the 2014 security incident.

Mayer has also offered to forgo any 2017 annual equity award as the breaches occurred during her tenure, Yahoo said.

Last month, Verizon Communications, which is in the process of buying Yahoo’s core assets, lowered its original offer by $350 million to $4.48 billion.

About the Author
By Reuters
See full bioRight Arrow Button Icon
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Leadership
  • Success
  • Tech
  • Asia
  • Europe
  • Environment
  • Fortune Crypto
  • Health
  • Retail
  • Lifestyle
  • Politics
  • Newsletters
  • Magazine
  • Features
  • Commentary
  • Mpw
  • CEO Initiative
  • Conferences
  • Personal Finance
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map

© 2025 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.