Computer hackers swiped personal information from at least 500 million Yahoo accounts in what is believed to be the biggest digital break-in at an email provider.
The massive security breakdown disclosed Thursday poses new headaches for beleaguered Yahoo CEO Marissa Mayer as she scrambles to close a $4.8 billion sale to Verizon.
The breach dates back to late 2014, raising questions about the checks and balances within Yahoo – a fallen internet star that has been laying off staff and trimming expenses to counter a steep drop in revenue during the past eight years.
The Yahoo theft represents the most accounts ever stolen from a single email provider, according to computer security analyst Avivah Litan with the technology research firm Gartner Inc.
“It’s a shocking number,” Litan said. “This is a pretty big deal that is probably going to cost them tens of millions of dollars. Regulators and lawyers are going to have a field day with this one.”
Yahoo says it has more than 1 billion monthly users, although it hasn’t disclosed how many of those people have email accounts. In July, 161 million people worldwide used Yahoo email on personal computers, a 30 percent decline from the same time in 2014, according to the latest data from the research firm comScore.
The data stolen from Yahoo includes users’ names, email addresses, telephone numbers, birth dates, scrambled passwords, and the security questions – and answers – used to verify an accountholder’s identity. The company said the attacker didn’t get any information about its users’ bank accounts or credit and debit cards.