One of the most frequent questions we are asked at Comparitech is does a Mac need antivirus protection? If you are one of the many people running OS X who are not sure if you need security software or not read on.
Mac Malware

In a nutshell

  • Macs are vulnerable to some malware and it’s a growing problem, however they are still much more secure than Windows systems
  • Apple’s built in security system does a reasonable job at keeping malware at bay, if you want to beef up your protection you won’t go too far wrong with Bitdefender which scores highly in independent testing and won’t slow your devices as much as many antivirus products. If you want a cheaper option take a look at our TotalAV review.

The details

If you’ve got an iMac, Macbook, Mac Pro or Mac Mini, you may be thinking that you need to install an antivirus program to keep you safe and secure from the large range of threats you keep hearing about in the media.

But then again, you may have heard that malware only affects Windows systems.

So what is the truth?

As with most questions relating to security, the answer is not crystal clear, but this article should help you gain a better understanding of how the land lies.

So, first things first, does malware exist on the OS X platform?

The answer to that is yes, it does, but not on a scale that should be keeping you awake at night.

OS X Malware

While your Mac most definitely can be infected with malware, Apple’s baked-in file quarantine and known malware checking abilities do a pretty darn good job at reducing the risks associated with downloading and running malicious code.

Whether those abilities are present in the version of OS X that you are running will likely depend on how old your Mac is and whether you’ve been upgrading the operating system along the way (if you haven’t, you really should you know) – malware detection was introduced with OS X 10.6 (Snow Leopard).

It operates in a way that many of you will know to be very similar to the antivirus programs that Windows users rely upon so heavily, quarantining content downloaded from the internet, using Code Signing certificates to verify the legitimacy of that content, and regularly downloading security updates that refresh a database of known threats targeting the Mac’s operating system.

Whenever you attempt to open files downloaded by a quarantine-aware application (some examples of which are Safari, Messages and Mail), you will be presented with a dialog box which will remind you what you are opening, where you downloaded it from, and at what time. If everything checks out you can continue to open it, otherwise you can cancel it.

Should you try and open a file that is known to be malicious, OS X from Snow Leopard onward will interrupt you with an alert box which will remind you what file you are trying to open, where you downloaded it from and at what time, along with a description of the issue it presents.

If the alert says the file is malware and will damage your computer you should, of course, move it to trash or, if it is a disk image, eject it.

Assuming you pay heed to those warnings and don’t open malicious files your Mac should stay virus free.

Key to that ideal, though, is your Mac malware database – you’ll need to keep it updated.

To do that, simply follow these 3 tips:

1. Click on the Apple icon found in the top left corner of your screen and then on System Preferences.


2. Open the App Store.


3. Lastly, ensure that the tick boxes next to ALL the update options are checked, as seen in the image below.


At this point, you are now fairly safe from malware, though it is important to note that you are not completely invulnerable.

Some threats may attempt to trick you into escalating admin privileges to install them – if you do, it’s already too late for antivirus to save you.

And zero-day threats – new malware that could find its way onto your system before Apple updates its databases – still pose a threat. And there is no doubting the fact that the Mac’s rise in popularity certainly makes it a juicer target for attackers than in years gone by.

For that reason alone you may want to consider installing some security software and my personal recommendation would be Bitdefender Antivirus for Mac which scores 100% for malware protection in AV-TEST’s independent testing and has a much lower impact on system resource usage than most other services. 

Beyond the unlikely event of a virus taking hold of your Mac, the most likely threats you will face are adware and spyware and the best way of avoiding those, and other threats, is through taking basic but effective security steps such as these:

  • Ensure your Mac’s built-in firewall is enabled: System Preferences > Security > Firewall
  • Make sure “Open ‘safe’ files after downloading” is unchecked: Safari > Preferences > General
  • Disable Java in your browser: uncheck “Enable Java” in Safari > Preferences > Security
  • This may sound obvious, but never let anyone else have access to your Mac or install files on it on your behalf unless you know you can trust them
  • Never open email attachments or other files that you have received from unknown or dubious sources
  • Only ever install software from reputable sites you know you can trust, and avoid pirated software like the plague
  • Ensure your Mac, and all your local and online accounts, are protected with strong passwords made up of at least 8 characters which should include numbers, letters (both upper and lower case) and special characters
  • Keep your Mac and applications up to date at all times, and get those updates through the developers’ sites or the App Store, not from any pop-ups that may appear while you are surfing the web

Practice all of the above and you should never have to worry about any threats disrupting your enjoyment of your Mac, at least not at the time of writing. Of course things do change though, so make sure you keep abreast of the latest security news just in case.

Related: Want to do even more to improve you security and privacy? Checkout our roundup of the  Best VPNs for Mac users.