[HONG KONG] Yahoo! Inc is preparing to disclose a "massive" data breach of its main service, Recode reported, just as Verizon Communications Inc prepares to take over the ailing internet company's core assets.
The break-in was "widespread and serious" and is expected to be disclosed this week, the tech news website said, citing several anonymous sources close to the situation as saying.
Yahoo didn't respond to phone and e-mailed requests for comment outside of normal business hours.
Such a revelation would confirm earlier reports that the same hacker who'd stolen data from LinkedIn was now selling information from 200 million Yahoo accounts on a dark web marketplace.
The data up for sale included user names, scrambled passwords and birth dates and likely dated from 2012, Motherboard reported in August, citing the cyber-attacker, who went by the name Peace. Yahoo said at the time it was investigating the claim.
Reports of the security breach come just as chief executive officer Marissa Mayer is about to close a deal that ends the once-dominant internet firm's independence.
Verizon is acquiring its internet assets for US$4.8 billion, bringing the web portal together with longtime rival AOL.
The telecommunications company will pick up services that still draw 1 billion monthly users, including mail, news and sports content and financial tools.