The common wisdom states that Macs aren’t as susceptible to viruses as Windows PCs are. But why is this, exactly?
Of course, no system is flawless when it comes to security. It’s possible to get malware on a Mac just like any other computer. And while user habits definitely play a role, you’ll be glad to know your Mac is naturally protected from most threats. Let’s look at the ways macOS is built to resist viruses and other malware.
What Is Malware?
We often use the terms “malware” and “virus” interchangeably, but they refer to different types of attacks.
A proper computer virus damages your software by slowing it down, filling up the hard drive, or deleting important files. Viruses are hard to get rid of because they replicate themselves inside your operating system.
These days, most computers do a pretty good job of protecting against traditional viruses, but there are hosts of other software threats lurking in the shadows. The term malware refers to any malicious software, including:
- Adware: Malicious programs that spawn advertisements
- Spyware: Monitors your computer use and reports it to some entity
- Worms: Malware that spreads to other computers over a network
- Trojan horses: Dangerous programs that masquerade as useful ones
- Computer viruses
What Protects a Mac From Malware Infections?
You might have heard the claim that viruses don’t affect Macs. This isn’t true, as Macs can certainly get viruses . But we’ve all come across someone who’s used a Mac without antivirus software for years and never had a problem. You’ll struggle to find the same story from a Windows user.
There are a lot of factors at play here. Windows has made tremendous progress in terms of security in recent years, but macOS still benefits from unique advantages that make it less likely to get malware in the first place.
1. Apple Built macOS Using the Unix Platform
When Microsoft developed Windows, it built the OS upon its own unique software platform called MS-DOS. In contrast, Apple developed macOS (or Mac OS X at the time) using Unix, an open-source platform that had already been in use for years.
Unix is renowned for its stability and security features, many of which aren’t present in MS-DOS. Windows hasn’t used MS-DOS as its basis since Windows XP, but many parts of its security and architecture today are left over from those old days.
Meanwhile, Unix is open-source and has been used by a range of different companies in the development of macOS, Linux, the PlayStation 4, and even the firmware for gadgets like your router.
There are lots of people looking to fix vulnerabilities in Unix so they can make their own products more secure. Your Mac benefits from this group effort, whereas Windows PCs are solely dependent on Microsoft’s architecture.
2. Gatekeeper Scans New Apps to Ensure They’re Safe
If you’ve ever downloaded an app from outside the Mac App Store, you may have discovered you can’t open it after the download completes. This is due to a macOS security feature called Gatekeeper.
When you download new apps, Gatekeeper quarantines them and uses XProtect to scan the code for malware. If it finds any, Gatekeeper alerts you of the risk and doesn’t let you open the app. You can bypass Gatekeeper by holding Control and clicking an app, but you run the risk of infecting your Mac when you do so.
Even if the XProtect scan comes back clean, Gatekeeper might reject your app if it doesn’t trust the developer. By default, your Mac only lets you install apps from the Mac App Store or “identified developers.” This allows apps like Dropbox, Evernote, or Microsoft Office while blocking lesser-known developers. This is an example of Apple’s infamous “walled garden” approach.
3. macOS Separates Apps With Sandboxes
macOS makes use of sandboxing to limit what apps can do. This is the practice of a software provider putting up virtual barriers around third-party apps to keep them from accessing other apps or system files on your machine.
It’s one of the reasons a Mac is less flexible than a Windows PC, but these restrictions come with the payoff of tightened security. Third-party applications have limited access to core system files, making it difficult for malware to cause serious damage if it gets past Gatekeeper.
Since macOS Catalina, Mac apps need to request permission for each part of the system they want to access. This includes categories like Files and Folders, Screen Recording, Camera, Photos, and more.
Go to System Preferences > Security & Privacy > Privacy to see what is and isn’t allowed; you can revoke access for anything you’re unsure about.
4. SIP Provides an Added Layer of Protection
The OS hides important system files on your Mac so you can’t accidentally damage or move them. But it also guards important files behind a hidden defense, called System Integrity Protection (SIP).
SIP (present on OS X El Capitan and newer) stops you or anyone else from editing the system files on your Mac, which are often a prime target for malware. This makes it trickier for malware to infiltrate your operating system and compromise the security or performance of your Mac.
Just like Gatekeeper, you can bypass SIP if you need to. But most reputable developers design their apps to work alongside SIP, so you shouldn’t need to. See our full explanation on System Integrity Protection for more details.
5. There Are Still Far Fewer Macs Than Windows Computers
Although it doesn’t seem like a great defense, particularly since it’s outside of Apple’s control, your Mac is also protected by the fact that there are more Windows computers in the world than Macs. In fact, there are a lot more.
A virus designed to damage Windows doesn’t work against Macs. So criminal developers need to choose which platform they want to target. Since Windows is vastly more popular than macOS, it makes more sense to create Windows malware and attack a larger number of people.
This is exactly what happens. Fewer malware threats exist for the Mac because there’s far less to gain for people who create them. This principle, however flawed, is known as security through obscurity.
Do What You Can to Keep Your Mac Safe
The weakest link of any security system is the user. Your Mac does a great job at keeping malware away, but you can help it by exercising common sense as well. For example:
- Keep your Mac up-to-date to benefit from the latest security patches.
- Avoid opening email attachments or links from unknown senders.
- Don’t bypass security features to install apps from untrustworthy sources.
For additional protection, you might also consider installing antivirus software. There are lots of bad options out there, so take a look at the best free antivirus software for your Mac to make sure you install something reputable.