How To Check Your Mac For Viruses And Malware 2021

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Computer viruses hold a sweet spot between boring, everyday occurrences, dating back to the 70s, and dramatic, science fiction-fueled monsters that will haunt us in the digital world. Whether you want to know how to find virus on MacBook Air, MacBook Pro, or iMac, learning to keep your information safe first is necessary and easy, with a few tips from the professionals.

In this guide, we explain how to detect malware on Mac (both with virus checker software and manually), as well as how to protect your Mac from getting infected in the first place. 

Can your Mac get a virus? 

“Do you need a virus checker for Macs?” one may ask. The answer is yes, all computers, even Macs, are vulnerable to malware (short for malicious software). A popular malware virus of 2017 was embedded into a Word document — a Mac Word file, not a PC one. In 2018, Apple discovered flaws in their Intel processor chips that could lead to two kinds of very ambitious strains of Mac viruses too. It’s wild to think that even iPads and iPhones can contract malware.

While Apple takes a lot of security precautions, the level of protection depends on your knowledge of how to check for malware on Mac. 

Know what a Mac virus is

Most of us are familiar with recognizing what a virus looks like thanks to its atrocious design and alarming vocabulary. However, not all viruses take the shock-and-scare approach to getting on your Mac. The latest adware could be a Trojan hiding in one of your Xcode projects, which is hard to recognize and equally hard to delete. 

While Apple’s new M1 Macs are considered more secure than Intel-based models, they get viruses too. The infamous Silver Sparrow virus — disguised as the macOS Installer Javascript API — specifically targets Macs with M1 chips and is believed to have infected over 30k Macs at the time of writing. 

Mac viruses often take a form of a .dmg file, because it was created by Apple itself to help install good software on your computer. If you’re ever trying to download something you know is supposed to be an image, music, movie, or document, but you get a .dmg file instead — that is as red as a red flag gets in terms of viruses. Do yourself a favor and delete that file immediately.

How to know that your Mac is infected 

Before you learn how to find virus on Mac, get acquainted with the main signs of your Mac being infected. The common red flag is your Mac going slow — but don’t panic, your Mac could have performance issues for many reasons, including low RAM, resource-hungry apps, etc. Typically, apart from slow Mac, viruses will give you one of the following problems: 

  • New extensions just appeared in your browser from nowhere
  • Your browser homepage has changed
  • You’re being stalked by annoying ads and pop-ups 
  • You get security alerts as a result of Mac virus checking 
  • You can’t access your private files. 

How to scan your Mac for virus

Why virus scan for Mac is important? Because Macs are vulnerable. Malware, adware, spyware, malicious files, worms, trojans, phishing software, you name it, you should check for it.  

The old way of thinking was that because there are more PCs than Macs in the world, the “virus people” would focus on them instead of Macs. But, we’re not in the 2000s anymore. In fact, in 2018, Apple moved to the fourth position in global laptop shipments. This means Macs are no longer shiny white boxes that are meant for fun and entertainment. 

Not only do we run our businesses off Apple devices and different versions of macOS but we also store family photographs, send out sensitive info — and, thanks to cloud computing, each device is synchronized. This means you should have a reliable Mac virus checking tool. 

Run a Mac virus scan in one click 

So how do I check for malware on my Mac? There are two answers to this question — you can either inspect your Mac step by step manually or get it all done for you. If you want complete Mac security, there is no better tool than CleanMyMac X, which can effortlessly scan for all the latest viruses, malware, spyware, and more. Here’s how it works:  

  1. Open the app and click Smart Scan 
  2. Wait a few minutes
  3. Check the results of the Mac virus scan under Protection
  4. If the app has found any malicious files, click Remove to get rid of them. 

CleanMyMac X smart scan

 

Using a tool like CleanMyMac X makes getting rid of viruses, of all shapes and formats, very easy. After the scan, it tells you what it’s found and gives you the option to remove it completely right then and there. Additionally, it will give you all kinds of other great options on how to optimize your Mac’s performance and free up some storage space. 

How to do a virus scan on Mac manually

In an ideal world, scanning for viruses should be automatic and happen nearly continuously. In reality, you can consider yourself reasonably safe if you scan your Mac once a week. However, not everyone has a good virus checker. “So how do I run a security check on my Mac manually?” you may ask. Here are the top five things to do:

Clear downloads  

As we’ve mentioned before, .dmg files could be the source of Mac viruses. While everything you download, including .dmg, typically goes into the Downloads folder, it’s smart to clear it first. Go to Finder > Downloads and delete the files you no longer need from there. 

Check for browser extensions 

The second step you should take is to check for browser hijackers and adware extensions: 

  1. Go to Safari > Preferences. See what the Homepage URL is currently set to and correct it if needed
  2. Then proceed to the Extensions tab and uninstall any you don’t recognize, as they could spy on you, save your private data, and redirect you to their malicious websites.

Remove suspicious apps

See whether you have applications installed that you don’t recognize:

  1. Go to the Applications folder via Go > Applications in Finder or using the shortcut Shift + Command + A
  2. Scroll through the list and delete any unknown applications
  3. Then empty the Bin.

Delete suspicious login items

Another step on your “malware removal Mac” mission is to remove any login items that act strange. Maybe you don’t recognize some of them or you don’t remember enabling them. Here’s how to stop these items from launching on startup: Apple menu > System Preferences > Users & Groups > Login Items > uncheck the boxes.  

Delete suspicious login items

Create a new profile in macOS 

If a Mac virus seems to be targeting the user and not the device, you can solve the problem by creating a new profile in macOS. To add a new user profile, do the following: 

  1. Go to the Apple menu > System Preferences > Users & Groups
  2. Unlock the page to make changes
  3. Click the plus button and choose the type of user you want to add (admin or standard)
  4. Add a new user name, password, and click Create User. 

How to stop viruses from stealing your data

It’s a common misconception that viruses only happen to people who are gullible, ignorant, or technologically illiterate. The stigma is that hackers prey on people, when in reality, they prey on behavior. Our basic assumption with Macs is that we expect Apple and our applications to have done all the security work for us. In truth, every user has to adjust their own behavior when using their Mac. 

Do you use public WiFi? Consider getting a Virtual Private Network (VPN) to encrypt the connection between your laptop and the external network. Shimo is a great VPN manager app that will help you here. While using it, raw information (whether sensitive or not) can’t be fed to any malicious programs lurking on your Mac, and hackers on the same network won’t be able to decode anything you’re working on. 

ClearVPN will help you block access to malware sites, which is a great security precaution. You can also use this stellar VPN app to remain anonymous online at all times and encrypt your connection.  

clear vpn mac

Speaking of encryption, Macs using OS X Lion and later come with the option to encrypt their hard drives using FileVault 2. Although encryption won’t prevent viruses from entering your computer (for that, you’ll need a scanner), it would still be very helpful in stopping viruses from stealing your information. To turn on FileVault: 

  1. Go to System Preferences
  2. Select Security & Privacy
  3. Navigate to the FileVault tab
  4. Choose Turn On FileVault. 

Keep your Mac secure and virus-free

Unfortunately, viruses don’t live in an easy-to-find location like your computer’s desktop. They can be embedded within an application, most notably, your favorite web browser, where it’s easier for them to view what you’re viewing and track what you’re typing. If you kept on seeing weird websites taking over your search bar, it's a sign that your browser has been hijacked. Other applications can get corrupted or infected too, especially if they have particularly weak security systems. Another example could be an email app you use or an open-source application that is behind on its patch upgrades. Check out how to get rid of malware on mac

If you think one of your applications is infected, a typical knee-jerk reaction would be to delete the whole thing and redownload it. Often, this will do the trick, but there are simpler solutions available. Clearing the application's cache should always be your first step, and, if there are optional hidden files, consider removing them as well.

To remove an application’s cache and get rid of Mac malware from the Library folder:

  1. Open Finder > Go > Go to Folder
  2. Type ~/Library/Caches and choose Go
  3. Delete any particular files inside the folder. 

If you are unsure about deleting cache files manually, use CleanMyMac X:

  1. Open CleanMyMac X
  2. Go to System Junk and click Scan
  3. When the scan is complete, choose Review Details
  4. Select User Cache Files and pick the caches you’d like to delete
  5. Click Remove.  

Unfortunately, not all viruses are easy-to-understand files that just sit on your computer. Sometimes they are root certificates that intercept your passwords and messages and send a copy to hackers. To effectively secure yourself from this, only download apps with valid developer certificates. Which ones are those? It’s hard to know but Apple built a feature that could help you here. 

  1. Go to System Preferences
  2. Select Security & Privacy
  3. In the “Allow apps downloaded from” select App Store and identified developers.

privacy security mac

Finally, keep an eye on your Mac’s performance 24/7 with iStat Menus. This will allow you to identify malware threats as early as possible. iStat Menus is a system monitoring tool that lives in your menu bar, with real-time insights about your Mac. CPU, network, disk load, resource-hungry apps, iStat knows more than you do about how your Mac performs. So when it slows down because of malware, this app will alert you first. 

istat menus mac

 You are well on your way to being protected from malware now. But, the truth is, simply avoiding viruses is not enough. You need to be proactive and know how to check for malware on Mac. 

As mentioned above, hackers who want to steal your information don’t target you specifically, they target your behavior. So, with this in mind, change your behavior when it comes to using your Mac in potentially unsafe ways. 

 Arm your computer with encryption tools (like FileVault and a VPN), so that your information can’t be stolen. Practice a healthy dose of skepticism when downloading files. But, most importantly, get professional apps like CleanMyMac, iStat Menus, ClearVPN, and Shimo — all of which are available on Setapp for your to try free. So get a scan now and see what it says.

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