Verizon Says All 3 Billion Yahoo Accounts Were Compromised in 2013 Attack

Yahoo's massive data breach that occurred in August of 2013 affected all three billion Yahoo accounts that existed at the time, Yahoo parent company Verizon disclosed today in a statement on, the website for the brand that now encompasses both AOL and Yahoo.

Previously, Yahoo said the hack affected 1 billion accounts, or a third of all accounts at the time. Verizon now says new intelligence suggests the attack was much larger, compromising all Yahoo accounts in 2013.

Subsequent to Yahoo's acquisition by Verizon, and during integration, the company recently obtained new intelligence and now believes, following an investigation with the assistance of outside forensic experts, that all Yahoo user accounts were affected by the August 2013 theft.
Information stolen from affected accounts included names, email addresses, telephone numbers, birth dates, hashed passwords, and both encrypted and unencrypted security questions and answers. Clear text passwords, bank account information, and credit/debit card information are not believed to have been accessed in the attack.

In a statement, Verizon says the Yahoo team is continuing to take significant steps to enhance security.
"Verizon is committed to the highest standards of accountability and transparency, and we proactively work to ensure the safety and security of our users and networks in an evolving landscape of online threats," said Chandra McMahon, Chief Information Security Officer, Verizon. "Our investment in Yahoo is allowing that team to continue to take significant steps to enhance their security, as well as benefit from Verizon's experience and resources."
Yahoo initially uncovered the attack after law enforcement officials provided the company with Yahoo user data from an unknown source. Yahoo notified users it believed were affected in 2016 at the time the attack was disclosed, but the company will now send email notifications to additional user accounts affected by the hack.

Along with the attack in 2013, Yahoo saw another data breach in 2014 that compromised 500 million accounts, and a third major breach targeting accounts between 2015 and 2016.

The security breaches affected Verizon's $4.48 billion June acquisition of Yahoo, leading Yahoo to drop its asking price by $350 million.

Yahoo is already under SEC investigation for not disclosing the data breach sooner and affected victims have been given the right to sue the company.

Tag: Yahoo

Top Rated Comments

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31 months ago
*whistling while Marissa Mayor floats away in her golden parachute*
Rating: 32 Votes
31 months ago
Rule #1: They’re always lying

This was intentionally slow-walked to get past the acquisition.

*whistling while Marissa Mayor floats away in her golden parachute*

I’ll bet she knew the whole time. Disgraceful.

She needs to be called before Congress: ('')

Drop these Members on the Committee a line and get her put in the hot seat.
Rating: 25 Votes
31 months ago
What's more shocking is that Y actually had 3 billion accounts
Rating: 16 Votes
31 months ago
How Yahoo handles the issue is the far bigger scandal.
Rating: 13 Votes
31 months ago

I believe there was a study some time ago showing the average intelligence and income of Yahoo users was lower than that of the other main competitors.

Published alongside the study that showed that people like to make crap up on the internet? Yeah. I think I remember it.
Rating: 11 Votes
31 months ago
It was just easier to say that all accounts were compromised.
Rating: 8 Votes
31 months ago

How Yahoo handles the issue is the far bigger scandal.

Could be indicative of a pattern of behaviour in the corporate world. First Yahoo’s (mis)handling, and then Equifax’s. Not surprising, though. Profits trump all else with that mindset.
Rating: 6 Votes
31 months ago
Slow clap for Marissa Mayer. I hope she faces some stiff penalties for what was clearly a deliberate scheme to keep the truth from being known for so long. It doesn't take four years to uncover the fact that your entire system of user accounts was breached. Four months, perhaps; but it would not have taken them four years to know that information.
Rating: 6 Votes
31 months ago
Marissa Mayer single-handedly took a company that was once respected and brought it to the butt of jokes everywhere....she becomes CEO, makes everyone working from home now work at the office, turns her office in to a giant daycare, employs writers that don't have the fundamental basics of the concept of proofreading and grammar, turns nearly every Yahoo story into a link to other news site stories, plasters the front page with sponsored ads masquerading as stories, not to mention every other story headline is "broke the Internet" stories or trash stories on celebrities and things no one really gives a crap about.

Other than that, she did a great job as a CEO.
Rating: 5 Votes
31 months ago
I think the most annoying aspect is the fact that I can not change my Apple ID and am stuck with the horrible 80 spam emails a day for this Yahoo! account.
Rating: 4 Votes

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