The actual number of stolen accounts in a recently unveiled hack of Yahoo! Inc.’s data systems may exceed 1 billion, much bigger than 500 million announced by the company, according to a report published by Business Insider citing an ex Yahoo executive with the knowledge of tech giant’s security practices.
The former executive said the company’s products use only a single user database to authenticate its users, and at the time of hack in 2014, the database kept personal data of up to 1 billion active users.
Yahoo hasn’t revealed the number of hack alert emails it sent to the affected users.
The breach is another setback for CEO Marissa Mayer, who failed to turnaround the Sunnyvale, California-based company and at last decided to sell its core internet business to Verizon Communications in a deal valued at $4.8 billion. However, it is unclear if the latest hack will affect the sale process.
Yahoo shares opened at $42.74 on Friday, and after hitting an intra-day high of $43.25 and an intra-day low of $42.72, finally ended the day at $43.10. The 52-week range of the stock is $26.15-$44.92. The company’s market cap is $41.53 billion.