How to tell if your computer was hacked and what to do

Your computer can be a kind of vault: valuable information such as passwords and bank account data is stored in it. However it is as if this safe was not totally safe as it is subject to hacker attack.

The latest example of a major hacking action happened on Friday in one of the most serious attacks to hit the United States in the last ten years. The action targeted on sites like Spotify, Airbnb and Twitter and affected millions of users.

But not all attacks are so obvious. In some cases, users have their passwords stolen and shared with other people or groups, which allows them to steal their digital identities and even money. When you realize what happened, it’s late.

Silent attacks

Jim Wheeler, former director of cyber-operations at Protection Group International (PGI), a security company based in Britain, explained that any computer or digital account could be hacked.

The problem is that home users and businesses often do not know they are being attacked.

“In 60% of cases, the victims only find out later and through a third person (who transmitted the virus) or an institution (such as the bank),” Wheeler said.

According to the expert, in some cases, users only notice when they attempt to access an account and can not or when the computer slows down. It is usually difficult to notice.

Ángel Bahamontes, a computer forensic specialist and president of Spain’s National Association of Computer Judges and Experts, agrees with Wheeler.

“There are a lot of things that can be measured and sometimes not. Many attacks are quiet (like trojan horses), and when you try to solve the problem, the damage is already done,” he said.

Change of passwords

The most common mistake is to use the same password (which is often no longer very secure) across multiple sites. And hackers take advantage of that. But there is a way to contain the damage until after an attack: change the password immediately.

Information scientist Jeremiah Onaolapo and his colleagues at University College London came to this conclusion after an experiment in which they created one hundred accounts for Google’s email service, Gmail, and shared those accounts on sites where they could be hacked.

They found that the pirates did not act immediately but waited a few minutes. This time is very important so that the user can protect themselves by changing the password.

“It’s critical that the user include letters and numbers. The longer and more complex the better,” explained Wheeler.

But here comes another problem: how to remember such complicated passwords?

A good idea might be to use the password manager, a program that allows you to store all of them securely. One of Wheeler’s suggestions is LastPass, which is free.

Claudio Chifla, a judicial computer expert, says that “we should not give anyone access to our passwords, and the ones we use should not have personal data (such as the name of the pet or the date of birth).

“It is recommended that passwords be made up of letters and numbers that do not repeat and that at least one of the letters is a capital letter,” he added.

No unnecessary risks

“Among other important measures, it’s using two-step identity verification systems and keeping your system up-to-date (the computer and the browser),” Wheeler warned.

“You always have to use programs with original licenses purchased and downloaded from official pages, from reliable sources,” added Chifla.

According to the expert, it is also better “to avoid opening strange emails and not clicking links and unknown pages.”

“Usually we realize that we’ve been hacked because our contacts get some weird email from our email box. Another classic sign is when our computer revenue drops or advertising pages start to open at random.”

“A great danger is that our device will be used without our knowledge to commit crimes.”

To prevent this from happening, Wheeler recalls another important move: not to publish much personal information on social networks.

“Think of it as if you were exposing your data to everyone in a mall,” he explained.

Prudence

Bahamontes believes that many hacking attacks only happen due to lack of prudence.

“People provide data without checking who they are asking for – for example, in free apps – downloading programs that put their computer at risk and depositing money into PayPal accounts that have been involved in fake promotions,” he explained.

“A lot of the attacks could be avoided with some care and common sense,” says Bahamontes.

For the expert, it is also important “to learn about cyber-security, with basic knowledge” to avoid attacks.

“It’s important for people to be more aware of the risks. Most often, neither the user nor the creator of the site where the attack took place notices that the hackers are acting,” Wheeler said.

“You do not have to be a genius to do a cyberattack. Even a 14-year-old can do it.”

The signs

According to the National Association of Cybersecurity and Technological Expertise (ANCITE) in Madrid, Spain, one of the main warning signs is the different behavior of the computer, with programs that stop working, files with changed content, sudden fluctuations in Internet connection or errors when accessing a service with your password.

Another is the appearance of additional toolbars in your browser (may be malicious software).

Be aware if advertising windows pop up frequently while you browse. Or if the anti-virus or anti-malware program stops working or appears to have been disabled.

When some of your contacts receive fake or advertising emails from your account, it’s also a sign of security breach.

And when you notice that data consumption has increased in your internet plan on the phone, be careful: it may be malware.

What to do?

ANCITE recommends that users periodically make backup copies of their files. If you save all this in the cloud, put passwords and do not rely on free services.

Use anti-virus and anti-malware programs and keep them up to date.

If you think that some hacker is using your computer remotely, immediately disconnect from the internet.

For smartphones, do not install applications that do not come from official websites of your operating system. Change your credentials to access the affected sites.

Enable 2-step verification to increase security. Never use the same password on different internet services and change these passwords without using personal and public data.