Contrary to popular belief, Macs do get viruses and other malware. Due to the way a Mac is constructed, the risk of that malware spreading is limited compared to the risk of it happening on a Windows device. But it’s still a serious threat — one that is getting worse by the day. So, you need to know how to check for malware on a Mac.
What does “malware” even mean?
Quite often, we switch between the terms “malware” and “virus.” Many people may believe that they are synonymous, but there’s actually a difference.
Malware refers to an all-encompassing category for many different kinds of threats against a computer and/or network. Included in that category are viruses, but other subcategories can include threats such as adware, spyware, scareware, ransomware, keyboard loggers, worms, and remote access trojans (RATs).
For the sake of simplicity, we will refer to viruses in this article as malware.
The common symptoms of a malware infection
Just like sneezing means you have a cold, there are typical symptoms of malware infection. Here are a few.
Your MacBook is slowing down to a crawl
Malware are greedy little creatures. Not only do they want all your data, but they also want all your CPU and memory. What they do on your device is very resource-intensive, and that requires all the memory capacity your device is capable of.
Some legitimate apps can take up a lot of CPU usage, but usually, shutting down non-essential apps can bring that CPU usage back down to a sustainable level. Even closing the Gmail tab in your browser can make a difference.
However, if nothing seems to make a difference, and your CPU and memory remain stubbornly above 90%, then you likely have a malicious app or script running in the background.
Your Wi-Fi connection is notoriously unstable
This, in itself, doesn’t always automatically mean malware. We all lose our Wi-Fi on a regular basis, and restarting the router usually fixes it in a jiffy. But if it’s turning off multiple times a day, maybe there might be something else at play here.
As we said, malware is resource-intensive. It needs your Wi-Fi to send its ill-gotten gains (your personal data) back to headquarters. Since it’s working so intensively, your Wi-Fi may be put to the test. Consequently, it may reach its limit and disconnect.
Suspicious installed apps are appearing
One common malware delivery method is malicious apps on your MacBook. These can arrive by either the malware installing them or you installing them from an unsafe source. These apps then coordinate the heist of your data.
If you find a strange app in your Finder’s Applications folder that you don’t remember installing, it needs to be removed immediately.
Your browser has developed a mind of its own
When you type “google.com” into the browser URL bar, the usual result is that you go to Google. Obvious, right? But what if you enter “google.com” and end up on a different web browser? A browser hijacker may be to blame.
With browser hijackers, hackers can redirect to an obviously different site or a cloned website that looks like the one you want to go to. Only if you look closely will you see that not everything is as it seems. If you have any unknown extensions on your browser, that is also a sign of browser hijacking.
You’re drowned by pop-up ads that want you to buy, buy, buy
One of the scourges of the internet is pop-ups. Users utterly hate them. That’s why ad blockers have become so popular.
For a hacker, however, pop-ups (known as adware or scareware) are the equivalent of a cash cow. By making the pop-up intimidating and dramatic enough, they can often get a lot of people to click it and buy whatever is being advertised. Not only could this result in a malware-infected file on your computer, but your personal details could also get stolen and used.
Can you get infected with a virus or other malware and not notice it?
It’s entirely possible to get a virus or other malware on your computer and not even realize it for quite some time.
Some people may think that pop-ups are a usual part of the internet and close them. Or they may also have an old computer that already runs slowly, so when it runs a bit slower, they think nothing of it.
So, yes, it’s possible that they may not realize that you have a virus or some other type of malware. But by educating yourself on what malware looks like and proactively scanning for it regularly with CleanMyMac powered by Moonlock, you can decrease the number of potential victims.
How to run a Mac virus scan
If you are convinced that you have malware on your Mac or you just want to check to be sure, you will need an antivirus solution. Macs have a built-in antivirus tool known as XProtect, but there’s no such thing as too much protection. Having an additional line of defense makes good cybersecurity sense.
CleanMyMac is a powerful tool for Mac that will detect and remove all types of malware, even the ones you may have thought couldn’t be removed, like ransomware.
Open CleanMyMac
If you’re using CleanMyMac for the first time, you should make sure you have it just the way you need it. Click Configure Scan and select everything. Make sure the Scan mode is set to Deep Scan to ensure that your MacBook is thoroughly checked.
Remember to enable the Malware monitor and the option to look for threats in the background. This turns CleanMyMac into a 24/7 malware detector and bodyguard that will warn you the moment malware is found.
Run CleanMyMac
Hit the Scan button, and CleanMyMac will start searching. Most software, at this point, would recommend that you go and make coffee. Not so with CleanMyMac. It’s a lightweight program, so it will do its work very quickly.
Review the results and delete
When the scan is finished, you’ll see a list of all the malware it has found. Select them all, and CleanMyMac will remove them for you.
How else can you check for malware on your Mac?
CleanMyMac, combined with macOS’s built-in security tools, is usually formidable enough against malware. But technically, there are some other methods to check for malware on your Mac.
Nothing beats a dedicated virus scan for Mac, and even if you do the following, it should ideally be followed by a CleanMyMac scan to be extra thorough.
Check your browser extensions
Earlier, we mentioned that browser hijackers typically use their own browser extensions. Back in the day, third-party toolbars were the usual weapon, but with third-party toolbars now virtually obsolete, apps have mostly stepped in to take their place.
It’s not just browser hijackers that can result in a malicious extension. If you sideload an extension onto your browser, this will bypass the browser security protocols. This is an important lesson on why you should never sideload.
By checking your browser extensions folder, you can quickly see if there’s anything you don’t recognize. If there is something there, remove it immediately. As a side note, you might want to run a web search for the name of the app first, just to make sure you didn’t install it yourself and forget about it.
You may also want to consider completely uninstalling the browser and then reinstalling it. But if you sync all your browser settings, take care not to accidentally reinstall the malicious extension.
Check your installed apps in Finder
In addition to browser extensions, apps are another popular malware delivery system. They can come from dishonest developers, or malware may be secretly bundled with legitimate software. It then installs itself in the background.
Check your Applications folder to see if there’s anything that screams malware.
Does Mac have a built-in virus protection scanner?
It’s worth remembering that macOS has its own built-in virus scanner. XProtect comes standard with every Mac. You don’t even have to enable anything or configure any settings. It scans your Mac for malware from the get-go automatically.
XProtect pulls its definitions from a signature database maintained and frequently updated by Apple, and it does a great job. However, XProtect may not catch everything, so having CleanMyMac as an insurance policy is a smart move.
Safeguarding your Mac from malware threats
As the saying goes, an ounce of prevention is worth a pound of cure. In other words, try not to have a malware problem at all by being proactive with your computer hygiene.
Install all macOS and app updates
Apple is good at providing timely updates to address known security vulnerabilities. But all they can do is provide them. It’s up to you to install them quickly.
New updates are usually time-sensitive. The hole needs to be plugged before criminals can exploit it. So, the longer you delay the updates, the more opportunity you’re providing cyber attackers.
Use a third-party antivirus software
Fortunately, you can use a third-party antivirus software to fill the gaps that XProtect misses. CleanMyMac is a trusted, affordable, highly rated, and extremely efficient antivirus platform. Users love it for being lightweight, fast, and very easy to use.
This is one antivirus platform without a learning curve.
Only use software in the App Store and from trusted developers
People sometimes complain about being shepherded to the Apple App Store to buy software there instead of through their preferred platform. But those same people forget that Apple is doing you a solid favor. The company is vetting and scanning those apps for threats — and blocking the problematic ones.
So, by limiting your software downloads to the App Store, you’re protecting yourself from the worst of the malware and decreasing your risk level considerably.
There are, of course, trusted third-party developers, such as MacPaw and Moonlock, that you can use. The major companies are generally trustworthy, but when it comes to smaller and lesser-known companies, use the App Store instead.
Be cautious when clicking links
If you only follow one piece of advice from this article on how to lower your risk of malware, let it be this: Be extremely careful about what links you click on.
We get it. You can’t refuse ALL links sent to you. But you should only click links sent to you by people you absolutely trust. If you get a link from a person you don’t know well — or don’t know at all — then the best course of action would be to ignore it.
Phishing links are sent out by email, SMS, chat message (like WhatsApp or Telegram). Alternatively, a hacker may send people to a website they control, where those same links are waiting.
Only visit HTTPS websites
Google did everyone a favor when they decided to prioritize sites with HTTPS security certificates. This had the effect of not only pushing malicious websites into the black hole of Google search results but also highlighting the dangers of normal HTTP websites.
That said, not every HTTPS website is automatically safe. Hackers can use fake security certificates to provide the illusion of safety and security. But, on the whole, HTTPS is much safer than HTTP. Simply look at the URL bar. Is there a padlock icon and HTTPS? Then you’re likely on a safe site.
Many browsers will actively block you from going to non-HTTPS websites. You can choose to ignore the warnings and override the blocks, but we advise against this.
Checking for malware on a Mac is something that should become second nature for every MacBook owner. Never be complacent or assume it could never happen to you.
Cyberattacks happen to everyone eventually. The only factor you can control is how quickly it’s stopped and, hopefully, destroyed. If you have CleanMyMac, powered by Moonlock Engine, that process will be quick, painless, and efficient.
This is an independent publication, and it has not been authorized, sponsored, or otherwise approved by Apple Inc. Mac, MacBook, and macOS are trademarks of Apple Inc.
