How to Tell If Your Computer Has Been Hacked

If it suddenly takes forever for your computer to boot up or for applications to open, you may have a malware infection. Malicious software, such as viruses, Trojans, and worms, runs in the background and uses a lot of your computer’s memory, slowing the device.

Your computer starts running slower

A compromised computer isn’t efficient, so instead of searching “how to check if I have been hacked” online, spend time paying attention to how your computer sounds and feels.

Your battery is drained and your fans go into hyperspeed

One of the creepier aspects of being hacked is noticing programs that seem to have a life of their own. Paige Hanson, chief of cyber safety education at NortonLifeLock, and Jeff Nathan, a security researcher with the company, consider this a warning sign of a hacked device.

Programs automatically connect to the Internet

When you attempt to browse the Internet anonymously, you’re trying to hide your activity from trackers. But you may want to hide your identity too. That’s because hackers can access your camera for nefarious purposes. A major red flag, according to cybersecurity expert David Geer? Your camera keeps starting by itself. (You’ll know it’s on by the indicator light.)

Your webcam randomly turns on

Raise your hand if you often pay attention to the lights on your router or modem. Good for you! The rest of us would benefit from giving our devices a glance every once in a while. They may tip us off that someone is controlling our computer.

You see unknown sending and receiving lights

Computer apps make our lives easier, but they can also be vehicles for malicious code aimed at collecting our data. That’s what’s known as an injection attack, and it often starts out as a request for data collection. As IBM explains, the code gives hackers the ability to execute remote commands.

Your apps act up

Has your Internet usage skyrocketed seemingly out of the blue? You’ve probably been hacked, says Ravichandran. If you pay for Internet access based on usage—say, if you connect to the Internet through your phone or pay for a certain amount of Internet access monthly—you’ll notice right away.

You notice unusually high Internet data consumption

“If all of a sudden you have browser add-ins or plug-ins you don’t remember installing, your machine may be infected,” says Richard Ford, PhD, chief scientist at cybersecurity company Forcepoint. “Often, these add-ins help an attacker monetize their access to your machine. Similarly, if the Web now seems full of pop-up advertisements, you may be infected.”

You start seeing more pop-up ads

The Internet of Things (IoT) aims to make life easier. Voice assistants can play music or tell you the weather. Machine-learning thermostats keep your environment comfortable. And smart locks secure your home. But IoT devices are “common targets for bad actors, as they don’t have space to run proper security systems and often store sensitive information like log-in details and passwords,” says Ravichandran.

Your smart devices act stupid

You may know all the ways Google is tracking you across the Internet. But something even more nefarious may be following your online activity if your browser has been hijacked.

Your homepage changed

You open a web browser, and faster than you can search “how to tell if my computer has been hacked,” you encounter websites that won’t work. It’s a red flag you’ve been hacked, says Trave Harmon, founder and CEO of Triton Technologies. “I’m not talking about one or two websites but multiple ones that aren’t related,” he says.

Websites and other tools stop responding

“If an antivirus warning pops up, don’t ignore it,” says Adam Dean, security specialist at GreyCastle Security. And don’t presume your antivirus software has removed the virus either. “If you see a malware detection by antivirus software, assume it’s letting you know you have an issue, not that it has deleted the virus,” he says.

You get a warning

You’ve failed to log in to Google. You can’t gain access to your Amazon account. And though you’re positive you’re using the correct password, you’re locked out of your health insurer’s site. According to Ravichandran, if none of your passwords seem to work, you’ve probably been hacked.

Passwords are not working

This situation is a bit tricky. It’s possible that your email account was hacked and not your computer. But if you notice giant group emails being sent from your account to every single person in your address book, it’s probably a sign that your computer was hacked.

Your account is sending mass emails