海角大神

Just three months after it said a "state-sponsored actor" compromised data from 500 million user accounts, Yahoo another incident that exposed听an estimated 1 billion people to criminal hackers.

The size of the intrusion is historic.听 recent have affected hundreds of millions of people, but not anywhere near 1听billion. Yet, the havoc wreaked on Americans' computer networks over the past few years听鈥� whether by听criminal hackers 辞谤听meddling intelligence agencies 鈥� makes even the Yahoo hack seem like little more than the latest plot development in a听long-running drama about digital听insecurity.

Yahoo hasn鈥檛 identified the intruders, who are said to have taken email addresses, encrypted passwords, names, dates of birth, and potentially unencrypted answers to security questions, but the company suspects a government-supported group is involved.听Yahoo said it doesn鈥檛 believe that credit card information or bank account data was affected by this breach, and is careful to note that unencrypted passwords don鈥檛 seem to have been taken.

So what should the many people affected by this massive hack do to protect themselves now?

Responding to hacks can sometimes feel like an exercise in futility.听Most people have had their information exposed in one way or another from the many data breaches that have affected government agencies, global , popular websites, and seemingly every other business connected to the internet.

For many, digital security听malaise has set in. Even so, these hacks shouldn鈥檛 just be ignored, because there are still ways to mitigate their impact.

Yahoo said in an email to users that it has already responded to the intrusion by requiring affected听users to change their听passwords and invalidate security questions. This should prevent whoever compromised these accounts from continuing to access them.

But even if criminals can't reuse passwords on other accounts, they may use information gained from security credentials to target Yahoo customers with scam emails.听Experts have cautioned听vigilance against fake tech support scams that have duped Yahoo users in the past.听

Whoever gained access to Yahoo accounts could also use stolen information to tailor attacks to听other听targets, too. This approach is known as spear-phishing: Instead of sending a generic email to many people, attackers can听increase their odds of success by going after specific individuals.听In fact, experts say the Office of Personnel Management hack may have led to听spear-phishing attacks.听

Attackers can also take information from emails about family members or coworkers to design sophisticated phishing attacks. That's why cybersecurity experts often caution against writing about sensitive issues in email services that are stored听in perpetuity.

Instead, many experts suggest, people may want to use encrypted messaging apps such as Signal, take advantage of ephemeral听features in tools like Facebook Messenger, and save听truly private chatter for in-person meetings.听

Data breaches also tend to have ripple effects across other internet platforms because people tend to听reuse听the same username and password combinations. If that's something you've been doing, now is a good time to change that habit.

Of course, after a data breach it's always听good听to reevaluate online security practices. One easy way to prevent someone from accessing an online account with stolen credentials is to set up two-factor authentication.

The tech advocacy group the Electronic Frontier Foundation for enabling two-factor authentication on Yahoo accounts just two days before Yahoo disclosed this latest data breach.

But some experts say even听that's not听enough, especially in regards to Yahoo.听Bret Lowry, chief executive of the WinPatrol security company, said in an email to Passcode that it鈥檚 time for Yahoo users to stop trusting the company with their data and delete their accounts.

"Especially disturbing is the time it has taken Yahoo to realize and announce the attacks," Mr. Lowry said. "Three years is forever in terms of computers and the internet. Yet that is how long it has taken Yahoo to make this information public, thus putting at risk every single account all of their users have on any site on the Internet, their [personal] computers, and at every business where people access their Yahoo accounts."

Lowry recommends manually deleting every email and folder, changing the answers to security questions, and generating a unique password for a Yahoo account before deleting it. That鈥檚 because deactivated accounts aren鈥檛 always removed from Yahoo鈥檚 servers, according to WinPatrol鈥檚 findings, and it鈥檚 better not to trust Yahoo to delete information before it can be compromised again.

He also said that people who connect their mobile phones to their Yahoo accounts 鈥� something the company has been pushing in recent years 鈥� should be on the lookout for mobile phishing attacks. Even deleting your account isn鈥檛 enough to be safe.

It鈥檚 going to take some time for the full effects of Yahoo鈥檚 data breaches to be known.听Perhaps the only thing anyone can do now is operate under the assumption that if something can be hacked it will be hacked.

Going forward, Adam Levin, founder of the identity protection IDT911, people should actually be more dishonest when setting up security for sites they use. When asked your mother's real maiden name, make one up, Mr. Levin suggested.

"Changing the answers to your security questions on Yahoo and all other accounts is a good first step, but it鈥檚 far from enough," he said. "Users should lie when providing new answers. It's not about veracity. It's about consistency."

But, he cautioned, "Just make sure听you aren't so creative in your answers that you can't remember them and lock yourself out."