Mac Malware Detections Dropped 38% in 2020, Most Still Adware

Antivirus software developer Malwarebytes today shared its 2021 State of Malware Report, which found that malware threat detections on Macs fell a total of 38 percent in 2020.

In 2019 Malwarebytes detected a total of 120,855,305 threats, which dropped to 75,285,427 threats in 2020. Consumer threats were down 40 percent, but as businesses operated remotely and shifted to online work, threat detections for business users grew 31 percent.

mac malware 2020
There was a drop in detections of Adware and potentially unwanted programs (PUPs), but Malwarebytes says that malware, which includes backdoors, data stealers, and cryptocurrency stealers/miners, increased by more than 61 percent.

That number sounds high, but malware still only accounted for 1.5 percent of all threat detections on the Mac, with the rest still coming from Adware and PUPs.

Potentially unwanted software represented more than 76 percent of detection in 2020, while Adware represented approximately 22 percent. These are overall numbers, and the breakdowns varied somewhat by country, but most Malwarebytes users are in the United States. Business machines saw a bit more malware and adware, with less unwanted software.

Of malware found on Macs, the top 10 malware families accounted for more than 99 percent of the total, with more than 80 percent detected due to suspicious behaviors. OSX.FakeFileOpener, malicious apps designed to open files, accounted for the second highest number of detections.

top mac malware 2020
Malwarebytes says that the most unusual Malware detected on Macs in 2020 was ThiefQuest, which spread through installers found on torrent sites. When infected, Macs would start to have files encrypted, with the malware providing ransom instructions.

These instructions went nowhere, though, and didn't provide a legitimate contact for removing the encryption. Instead, the ransomware was a cover for something more malicious.

Upon further investigation, we learned that the ransomware activity was really a cover for massive data exfiltration, including MS Office and Apple iWork documents, PDF files, images, cryptocurrency wallets, and more. This kind of malware, known in the Windows world as a "wiper," had never before been seen on Macs.

Even more interesting, the malware would inject malicious code into executable files found in the Users folder, such as components of Google Software Update, in a virus- like manner, another rarity in the Mac world. The combination of these features made ThiefQuest not only the most unusual Mac malware in 2020, but perhaps the most unusual Mac malware ever.

Sophisticated adware techniques were also spotted on Macs in 2020, including phishing for admin passwords, using synthetic clicks to automate browser extension installations, modifying the sudoers file to maintain root permissions indefinitely, and manually editing the TCC database to give the adware more system access.

On Macs, Malwarebytes says that the "business model of choice for most criminals" remains Adware, with trojans, worms, spyware, and RiskWareTools being more common on Windows machines. Still, malware is an increasing Mac problem and it's something that Mac users should be aware of.

Malwarebytes' full report can be read on the Malwarebytes website.

Popular Stories

Apple Logo Zoomed

Tim Cook Teases Plans for Apple's Upcoming 50th Anniversary

Thursday February 5, 2026 12:54 pm PST by
Apple turns 50 this year, and its CEO Tim Cook has promised to celebrate the milestone. The big day falls on April 1, 2026. "I've been unusually reflective lately about Apple because we have been working on what do we do to mark this moment," Cook told employees today, according to Bloomberg's Mark Gurman. "When you really stop and pause and think about the last 50 years, it makes your heart ...
wwdc sans text feature

Apple Rumored to Announce New Product on February 19

Thursday February 5, 2026 12:22 pm PST by
Apple plans to announce the iPhone 17e on Thursday, February 19, according to Macwelt, the German equivalent of Macworld. The report, citing industry sources, is available in English on Macworld. Apple announced the iPhone 16e on Wednesday, February 19 last year, so the iPhone 17e would be unveiled exactly one year later if this rumor is accurate. It is quite uncommon for Apple to unveil...
Finder Siri Feature

Why Apple's iOS 26.4 Siri Upgrade Will Be Bigger Than Originally Promised

Friday February 6, 2026 3:06 pm PST by
In the iOS 26.4 update that's coming this spring, Apple will introduce a new version of Siri that's going to overhaul how we interact with the personal assistant and what it's able to do. The iOS 26.4 version of Siri won't work like ChatGPT or Claude, but it will rely on large language models (LLMs) and has been updated from the ground up. Upgraded Architecture The next-generation...
iOS 26

iOS 26.3 and iOS 26.4 Will Add These New Features to Your iPhone

Tuesday February 3, 2026 7:47 am PST by
While the iOS 26.3 Release Candidate is now available ahead of a public release, the first iOS 26.4 beta is likely still at least a week away. Following beta testing, iOS 26.4 will likely be released to the general public in March or April. Below, we have recapped known or rumored iOS 26.3 and iOS 26.4 features so far. iOS 26.3 iPhone to Android Transfer Tool iOS 26.3 makes it easier...
iphone 17 pro dark blue 1

iPhone 18 Pro Max Rumored to Deliver Next-Level Battery Life

Friday February 6, 2026 5:14 am PST by
The iPhone 18 Pro Max will feature a bigger battery for continued best-in-class battery life, according to a known Weibo leaker. Citing supply chain information, the Weibo user known as "Digital Chat Station" said that the iPhone 18 Pro Max will have a battery capacity of 5,100 to 5,200 mAh. Combined with the efficiency improvements of the A20 Pro chip, made with TSMC's 2nm process, the...

Top Rated Comments

steve09090 Avatar
65 months ago
From the report.

Windows detections - 111,014,261 (down 12%)
Mac detections - 75,285,427 (down 38%)
Android detections show it getting much "nastier" and detections are increasing exponentially. (No overall numbers)
iOS detections - nothing reported Other than "it’s possible as some vulnerabilities exist"

That walled garden is looking quite lush...
Score: 16 Votes (Like | Disagree)
ArPe Avatar
65 months ago

what's the best solution to tackle malware or other harmful thinks on Mac? Any ideas? Any software I need to buy?
Stay away from torrent sites ?

Don’t install pirate apps ?

Stay away from illegal streaming sites ?

Stay away from crypto sites ?

Don’t click on shortened URLs sent or posted by anon accounts on social media ?

Don’t install more apps than you really need ?

Only use signed apps from well known developers ?
Score: 12 Votes (Like | Disagree)
ian87w Avatar
65 months ago
Sometimes I have to wonder people who have enough money to buy a Mac, but cheapen out on the software or content that they have to rely on pirate torrents.

I mean it’s understandable for a person who can barely afford $400 Windows laptop to take the piracy route. But I have a hard time feeling any sympathy for someone capable of affording $1k-$2k Mac yet being a cheapskate on software and content. With so many free apps available, and many apps being more affordable on mobile, piracy imo is more of personal choice nowadays.
Score: 10 Votes (Like | Disagree)
wanha Avatar
65 months ago

what's the best solution to tackle malware or other harmful thinks on Mac? Any ideas? Any software I need to buy?
An Apple engineer who was helping me with an unusual issue last year recommended Malwarebytes.

He said it is Apple support's go-to malware app in instances where one is needed (which, fortunately, is quite rare).
Score: 4 Votes (Like | Disagree)
LV426 Avatar
65 months ago

what's the best solution to tackle malware or other harmful thinks on Mac? Any ideas? Any software I need to buy?
The best solution is to install software from the App Store. If you do this, it is very unlikely you will have problems in the first place.

If you don't, be very careful indeed where you get your software. Don't go to torrent sites or such to get software. You're just asking for trouble if you do that. There are reputable software vendors who don't use the App Store, but you will need to take special measures on your machine to allow such programs to be installed. The default is to only allow App Store programs to be installed.

There are, of course, plenty of dodgy websites that will drop, or try to drop, installers onto your computer. A classic ruse is "Your Flash player is out of date. Click here to update". If you happen to get one of those installers, and try to run it, you'll get a system popup asking for your Mac login details before it allows the installation to proceed. You should, therefore, be very wary indeed if you ever see something like that, and cancel the installation.
Score: 4 Votes (Like | Disagree)
lkrupp Avatar
65 months ago

Often the person buying the computer is not the same person buying software. For example, children being issued Macs from school or given one by parents will sometimes have no way of obtaining some content or software so they resort to piracy. Additionally, some subscriptions are quite expensive. Adobe can charge hundred of dollars yearly, which is not a small amount even if you could afford Mac hardware.
Sounds to me like you are condoning piracy. If you can’t afford it it’s okay to steal it? Unfortunately that is the mentality that has been instilled in the culture over the years.
Score: 4 Votes (Like | Disagree)