Skip to Content
© Rawpixelimages | Dreamstime.com
How-tos

7 clear-cut signs your phone or computer is infected with a virus or keylogger

The smartest hackers aren’t the ones who hack the most systems — they’re the ones who never get caught. If they’re clever and stealthy enough, a hacker can leave your system filled to the brim with malware or weird ads, confuse your friends and relatives with shady emails, and even drain your bank account dry.

The worst part? It’s usually our poor cybersecurity practices that make hacks easier to pull off. And with the rising number of data breaches occurring each year, all signs point to even more attacks. Tap or click here for 5 security mistakes you’re probably making.

No matter what kind of device you’re using, a hacker with enough gumption and know-how can break in. Your best defense is knowing what to expect. Here are some surefire ways to know if your system has been hacked, and what you can do to fix or prevent it.

1. Slowed to a crawl and too hot to be bothered

© Mikovasa | Dreamstime.com

Malware tends to eat up a lot of system resources. After all, it’s an extra piece of unwanted software — one that intentionally runs your system dry. Programs on your computer can get sluggish or lag, and by the time you finally notice, it may already be too late.

If your computer is working overtime to handle the unwanted software, that can cause it to heat up. Needless to say, this can be dangerous for the health of your tech.

When a device gets too hot, internal components can melt or become damaged. Excessive heat also wears out the mechanical components of your device, such as its fans. A device that runs cool will last for much longer. Tap or click here to see how to keep your gadgets cool.

Here are some handy tools you can use to pinpoint nasty applications on your computer. If your desktop or laptop is running hot and a program you don’t recognize is hogging your system resources, there’s a good chance it’s malware.

PC: Use Task Manager

There are a few key ways to see what processes your computer is running. Windows gives users the ability to see them easily with the built-in Task Manager. Just use the keyboard shortcut CTRL + SHIFT + ESC to get to the Processes tab.

Windows’ Task Manager lists all of your computer’s current tasks, like programs, processes and app behavior, and how much processing power they’re using. This is usually measured in Central Processing Units, or CPUs.

To get started, open up Task Manager and check the CPU and memory columns for each process. You might find one program using 100%, or close to it, of your CPU. Open up the program associated with the process and see what it’s doing.

If you don’t recognize the name, Google it. Check online to make sure it’s a legitimate app or process; otherwise, restart the task and monitor it. If you see performance decrease again, you may have found your culprit.

Mac: Use Activity Monitor

The Mac equivalent to Task Manager is the Activity Monitor. And the quickest way to access Activity Monitor is by using Spotlight Search.

Click the magnifying glass on the right side of the menu bar at the top of your screen, or press Command + Spacebar to open a Spotlight window. Then, start typing the first few letters to auto-complete “Activity Monitor.” Press Enter to access the tool.

Similar to Windows’ Task Manager, Mac’s Activity Monitor displays a list of all your open processes with tabs for CPU, Threads, Idle Wake Ups and Network usage. If you see something using too many resources, research it, reset it and keep a close eye on it.

Smartphones

Are you experiencing sluggishness and heat on a smartphone? This isn’t always due to malware, though that could be the culprit. Smartphones tend to heat up and slow down with age, and processes that used to work smoothly can bog down the phone as updates become more demanding.

Consider how old your phone is before you jump to any conclusions. Still, ruling out malware can give you peace of mind. Your best bet is to reset the phone to clear out its memory banks. We’ll go over how to do this in more detail below.

2. You’re using way more data than usual

Adware-infected gadgets usually perform unsolicited clicks in the background to generate profits for cybercriminals. These stealthy tactics use up bandwidth and the unauthorized data they consume should be fairly easy to spot by simply checking usage stats. Here’s how to do it.

Every internet provider has tools that keep track of your monthly bandwidth consumption. Visit your service provider’s website, log in and go to the user portal.

Look at Data Usage Meter or Data Monitor, depending on your provider. Compare the amount of data used from the prior months. Small changes are normal, but if you notice sudden spikes in your data activity that doesn’t line up with your behavior, chances are you’re infected.

You can do the same check on your smartphone.

To check data usage on an Android, open the Settings app and tap Network & internet, followed by Data usage. Under Mobile, you’ll see how much data you’re using for the month.

To check data usage on iPhones, open the Settings app and tap Cellular. If you’re on an older version of iOS, open Settings and tap Mobile Data. You’ll see your cellular data listed under Usage, as well as the individual data usage for each app or service on your phone.

3. Videos refuse to buffer and webpages take forever to load

© Alejandro27 | Dreamstime.com

When a streaming video suddenly freezes and your device appears to be “thinking,” this is called buffering. Despite being annoying, it’s totally normal — especially if you play a lot of videos or your Wi-Fi connection is weak.

But if it’s happening often, or videos fail to play at all, you’re wise to suspect neighbors are piggy-backing on your connection. Tap or click here for steps on how to check for Wi-Fi thieves.

Malware can also slow down your internet traffic through a process called DNS hijacking. When this happens, hackers redirect your internet traffic to unsafe servers instead of secure ones. This will not only slow down your browsing experience, but it can also put your security at risk.

A good way to tell if your DNS settings have been hijacked is if the pages you end up on are different than the addresses you entered. Imagine attempting to visit your bank’s website and ending up on a shabby, typo-filled version of the page with no encryption. Red flag alert!

To check your router’s DNS settings, you can use online tools that also offer advanced hijacking protection, like CloudFlare or Quad9. Tap or click here to find out how to make your router hacker-proof.

4.  Programs and apps start crashing

Programs crashing frequently is a common sign things aren’t right. This goes double if your antivirus software and task manager are either crashing or disabled. This can mean a nasty virus has taken hold of your files.

In a worst-case scenario, ransomware-type malware can even prevent you from opening your favorite files. But a tried and true method to diagnose and fix the problem is booting your gadget in Safe Mode.

With Safe Mode, your computer runs with just the bare essentials. That way, you can safely delete and uninstall any programs and files you wouldn’t be able to access otherwise.

Windows:

On Windows, click the Windows logo key + I. This opens Settings. Choose Updage & Security, then Recovery. Under Advanced startup, choose Restart now. After your computer restarts to the Choose an option screen, click Troubleshoot > Advanced options > Startup Settings, then Restart.

After it restarts again, you’ll see a list of options. Choose 4 or press F4 to start in Safe Mode. If you need to use the internet, choose 5 or press F5 for Safe Mode with Networking. To exit Safe Mode, just restart your computer.

macOS:

On a Mac, start or restart your computer and immediately press and hold the Shift. Keep holding the key until the Apple logo appears and release when you see the login screen. To exit Safe Mode, restart your computer.

Android:

Android has its own version of Safe Mode. Due to the varying models of Android phones, each one has different steps. Learn how to access Safe Mode for your model here.

iOS:

iOS doesn’t have a Safe Mode, but you can try what’s called a soft reset to fix most issues. To do this on older iPhones, press and hold your iPhone’s Home button and the Sleep button at the same time. Wait for it to restart, then release the buttons when the Apple logo displays.

The iPhone X and later models don’t have Home buttons, so the process is a bit different. Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the side button and release when the Apple logo appears.

5. You start seeing pop-up ads

© Cacrov | Dreamstime.com

Malware can add bookmarks you don’t want, website shortcuts to your home screen that you didn’t create and spammy messages that entice you to click them. In addition to slowing down your gadget and eating away at your data, these intrusive notifications can also install more malware on your system.

Criminals can also use DNS hijacking to modify the ads you see while browsing. Instead of the normal sponsored ads you see all over the web, you might see pornographic or malicious ones. This is a huge red flag that somebody’s messed with your system.

On Windows, certain programs can help you eliminate adware and spyware. One example is Norton Power Eraser, which can help you find stubborn bits of software that antivirus programs can miss.

Since adware tends to embed itself deeply in other programs, Power Eraser is useful to clean out your system without harming other files. Tap or click here to learn more.

On a Mac, Malwarebytes for Mac gives you free system cleaning services and can help you remove problematic malware that hijacks the ads you see.

6. Your gadget suddenly restarts

Automatic restarts are part of normal tech life. Software updates and new application installs can prompt you to reboot your computer, tablet or phone. Your system will typically warn you when these resets happen, and you can usually delay or postpone them if they’re inconvenient.

But sudden restarts are a different story. Installing software usually requires you to reset your system, and a hacker installing malware may force a restart to complete the infection. If your PC experiences a sudden reboot for no apparent reason, it’s a good idea to perform a scan just in case.

With Windows 10, there’s a free malware detection and extraction program called Microsoft Windows Malicious Software Removal Tool. It’s part of Windows’ built-in security suite and is capable of finding and eliminating most threats.

The only catch is you need to keep Windows up to date to enjoy the latest malware protections and definitions. We recommend a full scan at least once a month to prevent your computer from running into trouble. After all, the only thing worse than a malware infection is letting one linger on your system.

7.  Unexplained online activity

It should come as no surprise that hackers are after your usernames and passwords. These details, coupled with social engineering tricks, can help them gain access to your banking accounts, social media profiles and just about every other part of your digital life.

Keep an eye on your email’s “sent” folder and on your social network posts. If you notice emails and posts you don’t remember sending or posting, you may have been hacked. Vigilance is key to staying safe.

You should check your accounts on a regular basis for unauthorized activity. This includes monitoring movies in your Netflix watch history, app and digital purchase history, songs on your Spotify playlists and, most importantly, your bank statements. Unknown charges are one of the biggest red flags of all.

If you find someone is pretending to be you and is buying things in your name, don’t panic. There are actions you can take, such as performing a credit freeze, that locks down your identity and can prevent anyone else from opening accounts in your name. Tap or click here to learn the benefits of a credit freeze.

In the end, our cybersecurity is only as strong as our will to enforce it. Let’s not give hackers a chance to mess things up.

Komando Community background

Join the Komando Community!

Get even more digital know-how and entertainment with the ad-free Komando Community! Watch or listen to The Kim Komando Show on your schedule, read Kim's eBooks for free, and get answers in the Tech Forum.

Join Now