Cybersec Essentials

How to Tell If Your Computer Has Been Hacked

Hacking, most of the times, isn't personal. Hackers carry out massive campaigns and you might just be unlucky! Learn how to detect it, and how to react.

August 11, 2021

Malicious hackers are after you. They want your personal information. They want control of your devices. They want your money. They want just about anything they can get their hands on. Scared? Hacking personal digital devices is a serious issue in cybersecurity, though it’s not always as threatening as you might imagine. In some cases, the legitimate concern is warranted. Other times, you’re dealing with a nuisance (but who wants that?).

Using reputable antivirus software is crucial to protect against malware, including fake antivirus software, Trojan attacks, and signs of a hacked computer.

This article focuses on how to tell if your computer has been hacked. Hacking can affect Macs, Windows 10 machines as well as iOS and Android devices. We discuss how to prevent hacking and stop hackers once they’ve invaded your life.

Has my computer been hacked?

Are you likely to suffer from a hack? Research suggests that it’s a definite possibility. According to Krebs on Security, consumers should contemplate two realities in effect today:

  • Reality #1: Hackers already have access to aspects of your personal data that you may believe should be secret, but which are not. These include your credit card info, social security, mother’s maiden name, date of birth and so forth.
  • Reality #2: Any data point you share with a business will almost certainly be hacked, lost, leaked, stolen or sold at some point in the future.

These may seem like depressing facts, but don’t fear, we’ve got some tips for you to find out if your computer is hacked and what to do to keep the damages at a minimum, including the use of robust security software.

Why do computers get hacked?

Hacking is, most of the time, a crime (don't confuse it with Ethical Hacking). Although it involves electrons, bits, and bytes, the hacker is breaking into your property. His or her goal may be simple malfeasance, as you might see with malware that slows your system for no discernable reason. While in other cases, hacking is the result of intelligence activity, with foreign governments trying to steal data about Americans and corporations. Mostly, though, hacking is a financially motivated crime. Hackers may target your bank accounts to make unauthorized transactions, leading to financial loss.

Forms of hacking

  • Identity theft – if a hacker can steal certain pieces of information about you, like your name, address, birth date and social security, he or she can impersonate you and take money out of your bank account or borrow money in your name (and not pay it back). Hackers can also make unauthorized transactions, leading to financial loss.

This is known as identity theft or identity fraud. It affects millions of Americans every year. Hackers steal identities by penetrating your digital devices and looking for your personally identifiable information (PII). They can accomplish their goal through malware that searches and exfiltrates your PII or through eavesdropping on messages you send. Typically, the hacker sells your PII to someone else, who then engages in identity fraud against you.

  • Phishing – in a phishing attack, the hacker tries to trick you into clicking onto a link in an email or text message that sends you to a website that either downloads malware onto your device or fools you into divulging personal information through a bogus web form.
    Phishing attacks have grown highly sophisticated, with the attackers creating perfect copies of websites for banks, airlines and so forth.
  • Spreading viruses and other malware – hackers frequently achieve their goals by spreading viruses and malware. A computer virus, like the biological organism it’s named for, takes up residence in your device’s hardware and software. Like a real virus, it steals resources from your legitimate use of the device and makes the device seem “sick,” i.e. slow or unresponsive. In some cases, a virus will be designed to destroy data in its path or even render a device completely unusable.
  • Malware, a related form of malicious software, is usually designed to carry a specific task. It might collect your data and send it off to the hacker. It might spy on your usage habits for a variety of malicious reasons.
  • Ransomware – this is a form of malware that encrypts your files, making them inaccessible to you unless you pay the hacker a ransom. Upon receipt of the ransom, usually demanded in cryptocurrency, the hacker unlocks your files so you can use them again. ‍
  • Cryptojacking – hackers sometimes take over your device so they can use it “mine” for cryptocurrencies like Bitcoin. Cryptocurrency mining is a mathematically intensive process that requires a huge number of CPU cycles. A hacker will embed malware in your system that uses your CPU and network connections to mine for cryptocurrencies.

How do hackers get into my computer?

In order to get malware onto your system, the hacker has to induce you to open a file that contains the malicious code. They accomplish this by sending you files that look legitimate, like Microsoft Office documents or PDFs that contain hidden code that infects your system.

You can also get malware from a USB stick or by visiting a website that loads the code onto your device over the web connection. Sometimes, the hacker has compromised a device somewhere else in the communication chain, like a router, so it can steal your data as it moves across the network. Hackers may also change your system settings to make it difficult for you to regain control of your device.

Signs that your computer has been hacked

Have you been hacked? Often, it’s hard to know for sure, but there are certain signs that someone has attacked your device. Checking the Task Manager for unfamiliar processes can also be a sign of hacking. Here are a few of them:

Using reputable antivirus software can help identify and remove malicious software. If you notice any of these signs, it’s crucial to take immediate action to secure your device.

Unusual Activity

If you notice unusual activity on your system, you may be a victim of hacking. Let’s say you find software installed, but you don’t remember doing the installation—that’s a classic sign of hacking. Other indicators of hacking include problems like having unknown processes running and high resource utilization.

Additionally, being unable to access key system settings like factory reset or system restore could indicate a hacking attempt.

Unprompted Actions

If your cursor moving on its own or watching words appear on the screen without you typing is also a tip-off that your device has been hijacked. If you're redirected from the results of an Internet search to another page without your action is another clue.

Random Pop Ups

If you see random pop-ups with false anti-virus messages telling you to hurry and download new software, you've probably been hacked.

Computer Performance Decline

One of the most common side effects of hacking is a sudden decline in performance. As the hackers use system resources like the CPU, memory, and bandwidth, there is less leftover for you. Your PC or Mac might be slow to respond to your inputs. It might take forever to boot up. At the same time, you might observe a huge amount of network traffic. Someone's using your device, just not you.

Unknown Social Media Requests

Lastly, if you receive random access notifications on social media accounts or other online accounts, you may have been hacked. Hackers frequently use non-technical means to steal your data. They pose as friends online. They call you and pretend to be from your Internet provider—all to get your system credentials and PII.

What to Do If Your Computer Has Been Hacked

Okay, so maybe your computer is showing one or all of the signs above. What do you do now?

If your computer has been hacked, the best practice is to quarantine it.

This may involve the use of anti-virus software, which has quarantine options. Then, you need to run a system scan and root out any malware it finds. Sometimes a basic system cleanse (e.g. CCleaner) can erase malware. If it’s a sophisticated attack, however, you may have to take things a lot further. Ensure that your cloud storage accounts are secure and change their passwords as well.

How to Remove Malicious Software:

Wipe and Reinstall

Removing a serious system takeover may require completely wiping your hard drive and reinstalling your operating system, but only use a trusted source. With this potential in mind, it's a wise practice to have a continuous, automated backup in effect through services like Carbonite. That way, if your system has to be erased, your files will still be intact.

Rebuild Your System

Ass you rebuild your system, change your passwords and add two-factor authentication.

Do a Quick Social Check

Check your email and social media accounts to make sure you haven't accidentally sent malware or fraudulent messages to your friends.

The importance of prevention

The prevention of hacking is a high-priority issue for businesses and government organizations. Data breaches and other destructive cyber incidents can be embarrassing and extremely costly to handle. Individuals should also put effort into preventing becoming victims of hacking.

Hacking is more than just a hassle. Victims of identity fraud, for example, may find themselves dealing with negative impacts on their credit ratings and so forth. Ransomware victims may be unable to work.

How to prevent your computer from being hacked

Preventing your devices from getting hacked is not difficult. There are no absolute protections, but some basic, consistent practices can do a great deal to protect you. We'll break them down a bit by operating systems and then provide some blanket tips.

Windows 10 / 11

One thing that’s essential is to keep your operating system software up to date. With PCs, this is usually automatic. Microsoft issues fix security flaws every week.

Windows actually has a security system built into their products. Windows Defender provides basic protection, but it's recommended to use additional security measures for enhanced protection. Windows 10 & 11 have the latest antivirus protection, and also offers 6 other areas of security. You’ll have account protection, firewall, and network protection, app & browser control, device security, performance & health, and family options. They’ve done a great job of updating their systems to provide every possible security.

Macs & Apple computers: Enable Two Factor Authentication

Use a router. If you connect your Mac to a public network (or broadband), it becomes public and is much more vulnerable to being hacked.

Update your system automatically. Apple continually updates its software to prevent hacks before they happen. Along these same lines, you can enable your Mac's firewall.

General Tips

Strong password practices are another countermeasure. Do not use the same password for every device and app. Keep your accounts secure with a variety of complex passwords. A strong, complex password is one that contains letters, numbers, capital letters, and symbols like $ and !

This difference in protection is remarkable when you add more diverse characters. According to, a six-character all lower case password can be cracked in 10 minutes. With the addition of two extra letters and some uppercase letters, that password will now take 3 years to crack. With the addition of characters, numbers, and symbols, it takes literally tens of thousands of years to crack.

Change passwords often. And, don't make a Word document called “passwords” and store it on your machine. That's the first thing hackers look for. Keep them on paper or secure them with a password manager.

Stay vigilant. Pay attention to what networks you connect to. For example, avoid using public WiFi. You'd be shocked at how easy it is for hackers to read what you're doing on your machine when you're on the WiFi at a coffee shop. The nice person at the next table could be a hacker. We recommend using VPN tools whenever you use public wifi.

Awareness is also your best protection against phishing and scam emails. We all know now to ignore the old “I'm an African prince” emails, but phishers today are infinitely more sophisticated. They might research you on social media and pose as your friends in order to trick you into divulging information.

Hacking is a widespread form of criminal activity. It affects millions of people around the world. Hackers usually want to steal your data in order to sell it. Or, they want to steal your computing resources for purposes like mining for cryptocurrency.

Signs that you've been hacked include degradation of system performance, odd cursor, and text and the appearance of software you didn't install. It is possible to prevent most hacking by using complex passwords, installing anti-virus software, and keeping current on your operating system software. Awareness is crucial. So many attacks arise out of human error. Stay alert and be vigilant about where you store sensitive information, the files you open, and links you click. If you are hacked, remediation might involve reinstalling your system software, however. Backups are recommended to preserve files in case of this eventuality.

Hopefully, this guide proves helpful as you navigate your way through the cyber world, where hacking is all too prevalent.

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