Yahoo Discloses Second Major Hack, More Than 1 Billion Accounts Compromised

Yahoo today announced that it believes more than one billion Yahoo user accounts were compromised in a hack by an unauthorized third party in August of 2013.

Information stolen from affected accounts includes 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 were not believed to be accessed in the attack.

yahoo
According to Yahoo, the hack was discovered after law enforcement officials provided the company with what appeared to be Yahoo user data from an unknown source. Yahoo says it has not been able to identify the specific intrusion, but it is "likely" distinct from a late 2014 hack that compromised more than 500 million Yahoo user accounts.

Earlier this year, Yahoo confirmed that "at least" 500 million user accounts were accessed in September of 2014, and this marks a second attack during the same general timeframe.

Yahoo is notifying users who may have been affected by the attack, and says it has "taken steps" to secure their accounts by implementing mandatory password changes. Unencrypted security questions and answers have also been invalidated.

Along with the 2013 hack compromising 1 billion user accounts, Yahoo has also announced that an ongoing outside investigation suggests an unauthorized third party accessed proprietary code to forge cookies, a technique that may have been used by the hackers responsible for the September 2014 attack. Those account holders are also being notified.

The outside forensic experts have identified user accounts for which they believe forged cookies were taken or used. Yahoo is notifying the affected account holders, and has invalidated the forged cookies. The company has connected some of this activity to the same state-sponsored actor believed to be responsible for the data theft the company disclosed on September 22, 2016.

Yahoo suggests users "review all of their online accounts" to check for suspicious activity and change any passwords that might have been used for a Yahoo account and another online account. Yahoo also recommends implementing two-factor authentication and avoiding links from suspicious emails.

Tag: Yahoo

Popular Stories

iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro to Reverse iPhone X Design Decision

Monday July 7, 2025 9:46 am PDT by
Since the iPhone X in 2017, all of Apple's highest-end iPhone models have featured either stainless steel or titanium frames, but it has now been rumored that this design decision will be coming to an end with the iPhone 17 Pro models later this year. In a post on Chinese social media platform Weibo today, the account Instant Digital said that the iPhone 17 Pro models will have an aluminum...
iOS 26 Feature

Everything New in iOS 26 Beta 3

Monday July 7, 2025 1:20 pm PDT by
Apple is continuing to refine and update iOS 26, and beta three features smaller changes than we saw in beta 2, plus further tweaks to the Liquid Glass design. Apple is gearing up for the next phase of beta testing, and the company has promised that a public beta is set to come out in July. Transparency In some apps like Apple Music, Podcasts, and the App Store, Apple has toned down the...
apple wallet drivers license feature iPhone 15 pro

Apple Says iPhone Driver's Licenses Will Expand to These 8 U.S. States

Tuesday July 8, 2025 11:26 am PDT by
In select U.S. states, residents can add their driver's license or state ID to the Wallet app on the iPhone and Apple Watch, providing a convenient and contactless way to display proof of identity or age at select airports and businesses, and in select apps. Unfortunately, this feature continues to roll out very slowly since it was announced in 2021, with only nine U.S. states, Puerto Rico,...
apple account card feature

Apple Account Card Expanding to More Countries

Tuesday July 8, 2025 7:34 pm PDT by
Apple is expanding the ability to add an Apple Account Card to the Wallet app to more countries, according to backend Apple Pay changes. With iOS 15.5, Apple updated the Wallet app to allow users to add an Apple Account Card, which displays the Apple credit balance associated with an Apple ID. If you receive an Apple gift card, for example, it is added to an Apple Account that is also...
iphone 16 pro ghost hand

5 Reasons to Skip This Year's iPhone 17 Pro

Thursday July 10, 2025 4:54 am PDT by
Apple will launch its new iPhone 17 series in two months, and the iPhone 17 Pro models are expected to get a new design for the rear casing and the camera area. But more significant changes to the lineup are not expected until next year, when the iPhone 18 models arrive. If you're thinking of trading in your iPhone for this year's latest, consider the following features rumored to be coming...
iPhone 17 Pro in Hand Feature Lowgo

Leaker Reveals Amount of RAM in iPhone 17 Through iPhone 17 Pro Max

Wednesday July 9, 2025 8:08 am PDT by
Three out of four iPhone 17 models will feature more RAM than the equivalent iPhone 16 models, according to a new leak that aligns with previous rumors. The all-new iPhone 17 Air, the iPhone 17 Pro, and the iPhone 17 Pro Max will each be equipped with 12GB of RAM, according to Fixed Focus Digital, an account with more than two million followers on Chinese social media platform Weibo. The...
iphone 16 pro models 1

Here's How the iPhone 17 Pro Max Will Compare to the iPhone 17 Pro

Saturday July 5, 2025 1:00 pm PDT by
Apple should unveil the iPhone 17 series in September, and there might be one bigger difference between the Pro and Pro Max models this year. As always, the Pro Max model will be larger than the Pro model:iPhone 17 Pro: 6.3-inch display iPhone 17 Pro Max: 6.9-inch displayGiven the Pro Max is physically larger than the Pro, it has more internal space, allowing for a larger battery and...
imac video apple feature

Apple Launching These 15+ Products Later This Year

Sunday July 6, 2025 8:05 am PDT by
The calendar has turned to July, meaning that 2025 is now more than half over. And while the summer months are often quiet for Apple, the company still has more than a dozen products coming later this year, according to rumors. Below, we have outlined at least 15 new Apple products that are expected to launch later this year, along with key rumored features for each. iPhone 17 Series iPho...

Top Rated Comments

keysofanxiety Avatar
112 months ago
Wow, Yahoo really does suck.
Score: 18 Votes (Like | Disagree)
Schwyz Avatar
112 months ago
Yahoo has 1 billion+ accounts?
Wait, what company are we talking about again?
Score: 16 Votes (Like | Disagree)
avanpelt Avatar
112 months ago
I wonder if Verizon has the ability to walk away from the merger without significant financial consequence at this point? This is akin to finding out that the person you're engaged to has been living a secret life as a prostitute for the past 10 years.
Score: 14 Votes (Like | Disagree)
ziggie216 Avatar
112 months ago
Being hacked is one thing, how they manage to sweep it under is another thing.
Score: 12 Votes (Like | Disagree)
oplix Avatar
112 months ago
CNN breaking news: it was the russians (confirmed by 34 intelligence agencies)
Score: 8 Votes (Like | Disagree)
yaxomoxay Avatar
112 months ago
Glory days!

I remember the battles trying to get my sites listed in yahoo. It was where you needed to be. The amount of traffic you'd start getting once listed in the yahoo index proper was such a thrill.
You could also get some attention via very modern methods:

Score: 7 Votes (Like | Disagree)