Fresh data from 2025 shows that Windows computers continue to attract the bulk of malware activity. Surfshark[1] Antivirus recorded close to 479,000 detections from January through late August. Out of that total, about 419,000 were on Windows devices and just over 60,000 were on macOS. The difference puts Windows at nearly seven times the number of infections seen on Apple systems.
Market Share Shapes Attacks
One reason behind the imbalance is the larger share of Windows in the desktop market. Globally, Windows accounts for around 71 percent of users, while macOS holds about 15 percent. The picture is similar across individual regions. In the United States and the United Kingdom, Windows has about two thirds of the share. In Germany, France, and Spain it ranges from 70 to 72 percent, while in South Korea it climbs as high as 85 percent. Attackers lean toward platforms that promise the widest reach, and the scale of Windows keeps it at the top of their list.
Malware Types on macOS
Although the raw numbers on Apple machines remain smaller, the data[2] makes clear that macOS faces its own risks. Viruses accounted for the largest portion at 28 percent. Trojans followed at 26 percent. Riskware came in at 15 percent, adware at 8 percent, and exploits at 7 percent, while the rest fell into less common categories. Each carries a different method of operation, from malicious code that attaches to programs to software that appears legitimate but opens a pathway for further attacks.
Windows Categories and July Surge
On Windows, the most common detections involved malicious PowerShell scripts, which made up 22 percent of the total. Trojans represented 21 percent, viruses 17 percent, heuristic detections 14 percent, and potentially unwanted applications 11 percent. The reliance on PowerShell was most visible in July, when detections rose to 100,000. That figure was more than double the monthly average of 47,000. More than half of those infections were linked to PowerShell-based attacks that coincided with known flaws in Microsoft’s SharePoint software. April and May also showed smaller peaks with 13,000 and 23,000 detections tied to the same method.
Importance of Timely Updates
MacOS did not show spikes of that scale, although some variation appeared, such as a rise in trojans during May. Even with fewer cases overall, the platform still recorded a share of threats designed to exploit unpatched systems. About 7 percent of detections on macOS fell into this category. This pattern underscores the need for users to keep their systems updated. Both Microsoft and Apple issue regular patches to close security gaps, and the data shows how quickly attackers try to take advantage of those who delay applying them.
Notes: This post was edited/created using GenAI tools.
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