Yahoo Inc (YHOO.O) said on Thursday that information from at least 500 million of its user accounts was stolen in 2014 by what it believed was a state-sponsored actor, a theft that appeared to the biggest cyber breach ever.

Cyber crooks may have stolen names, email addresses, telephone numbers, dates of birth and encrypted passwords, the company said. Unprotected passwords, payment card data and bank account information did not appear to have been compromised, Yahoo said, signaling that some of the most valuable user data was not taken.

“This is the biggest data breach ever,” said well-known cryptologist Bruce Schneier.

He said it was too early to say what impact the breach might have on Yahoo and its users because many questions remain, including the identity of the state-sponsored hackers behind it.

It was not immediately clearly when Yahoo learned of the hack and why it took two years to come to light.

The size of the attack on Yahoo was unprecedented compared to other corporate breaches such as at eBay Inc (EBAY.O) in 2014 which involved personal data of 145 million users… see more

source: huffingtonpost