China Daily

Yahoo suffers world’s biggest hack

- In San Francisco

Yahoo has discovered a 3-year-old security breach that enabled a hacker to compromise more than 1 billion user accounts, breaking the company’s own humiliatin­g record for the biggest security breach in history.

The digital heist disclosed on Wednesday occurred in August 2013, more than a year before a separate hack that Yahoo announced nearly three months ago. That breach affected at least 500 million users, which had been the most far-reaching hack until the latest revelation.

“It’s shocking,” said security expert Avivah Litan of Gartner Inc.

Both lapses occurred during the reign of Yahoo CEO Marissa Mayer, a once-lauded leader who found herself unable to turn around the company in the four years since her arrival. Earlier this year, Yahoo agreed to sell its digital operations to Verizon Communicat­ions for $4.8 billion a deal that may now be imperiled by the hacking revelation­s.

Two separate hacks

Yahoo didn’t say if it believes the same hacker might have pulled off two separate attacks. The Sunnyvale, California, company blamed the late 2014 attack on a hacker affiliated with an unidentifi­ed foreign government, but said it hasn’t been able to identify the source behind the 2013 intrusion.

Yahoo has more than a billion monthly active users, although some have multiple accounts and others have none at all. An unknown number of accounts were affected by both hacks.

In both attacks, the stolen informatio­n included names, email addresses, phone numbers, birth dates and security questions and answers. The company said it believes bank-account informatio­n and payment-card data were not affected.

But hackers also apparently stole passwords in both attacks. Technicall­y, those passwords should be secure; Yahoo said they were scrambled twice once by encryption and once by another technique called hashing. But hackers have become adept at cracking secured passwords by assembling­huge dictionari­es of similarly scrambled phrases and matching them against stolen password databases.

Questions for Verizon

That could mean trouble for any users who reused their Yahoo password for other online accounts. Yahoo is requiring users to change their passwords and invalidati­ng security questions so they can’t be used to hack into accounts.

News of the additional hack further jeopardize­s Yahoo’s plans to fall into Verizon’s arms. If the hacks cause a user backlash against Yahoo, the company’s services wouldn’t be as valuable to Verizon, raising the possibilit­y that the sale price might be renegotiat­ed or the deal may be called off. The telecom giant wants Yahoo and its many users to help it build a digital ad business.

After the news of the first hack broke, Verizon said it would re-evaluate its Yahoo deal and in a Wednesday statement said it will review the “new developmen­t before reaching any final conclusion­s”. Spokesman Bob Varettoni declined to answer further questions.

Investors appeared worried about the Verizon deal. Yahoo’s shares fell 96 cents, or 2 percent, to $39.95 after the disclosure of the latest hack.

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