In early 2018, a group of security specialists were asked which desktop operating system an enterprise should trust most. Their answer was close to unanimous: Linux, ahead of macOS and then Windows. The question mattered because companies spend heavily on firewalls, intrusion detection, SIEM tools and security operations centres, yet rarely ask whether the operating system on staff PCs was chosen with security in mind.
The comparison covered three families: Windows, the most widely used desktop platform; macOS, built on a Unix foundation derived from FreeBSD; and Linux, taken to mean the many distributions and related Unix-like systems.
Why the choice was rarely revisited
Most organisations settled on a desktop OS years earlier, when attacks were less organised and every platform looked reasonably safe. Moving a dispersed workforce to a different OS is a heavy undertaking, so the decision tended to stay put.
The threat picture had meanwhile changed. The lone amateur hacker had given way to organised criminal networks and state-backed groups with large computing resources. Botnets also meant attackers no longer needed to pick targets: hitting 100,000 machines took little more effort than hitting a dozen.
The OS matters, but it is not a guarantee
The experts stressed that the operating system was only one layer. A survey of attendees at the DEFCON conference found that 84 per cent used social engineering as part of their attack strategy, so breaches often began with people rather than software. User education, strong firewalls and constant vigilance were still needed.
Prompt patching was another point of agreement across all platforms, because attackers can study a released fix and build exploits against systems that have not applied it. Basic hygiene also counted: avoiding routine use of root, closing guest access on older servers, and giving users password managers so that each account has a different password.
Windows: the biggest target
NetMarketShare estimated in 2018 that 88 per cent of computers on the internet ran Windows. Microsoft had by then added its own antivirus, improved its firewall and introduced sandboxing, in which programs cannot reach the memory of the OS or of other applications.
Popularity was the problem. Troy Wilkinson, chief executive of Axiom Cyber Solutions, said Windows came last on security largely because its huge adoption made it the main target for attackers. Malware from Melissa to WannaCry had mostly been aimed at it.
macOS: safer, but not immune
Wilkinson judged macOS more secure than Windows, but warned that attackers had begun writing more exploits for it. Lee Muson, a security researcher at Comparitech, called macOS likely the best of the mainstream choices. He added that part of its edge came from being a smaller target than Microsoft’s platform, a form of security through obscurity.
That idea had long been discredited as a primary defence. Joe Moore of Wolf Solutions gave Apple more credit, saying macOS had a good out-of-the-box record because it was less widely targeted and because Apple stayed on top of security issues.
Linux: the case for the winner
The specialists named Linux the most secure option, while noting that it was the usual choice for servers and rarely deployed on enterprise desktops. Moore said it had the potential to be the most secure but expected users to be something of a power user.
Open source was central to the argument. Igor Bidenko, chief information security officer at Simplex Solutions, said anyone could inspect the code for bugs and back doors. Wilkinson said Linux and Unix-based systems had fewer known exploitable flaws, because the technical community reviewed the code and that oversight reduced vulnerabilities.
PC World’s Katherine Noyes made a related case. She argued that Microsoft’s paid developers could not match a global base of Linux contributors. She also pointed to the privilege model: Windows users were typically given administrator rights by default, whereas Linux restricts root far more tightly. In her view the variety of Linux distributions also worked against the monoculture that helped malware spread on Windows.
Distributions built for security
Choosing Linux still meant choosing a distribution, and users would expect a familiar interface. Moore pointed to Parrot Linux, a Debian-based distribution that ships with many security tools. Muson recommended Qubes OS as a starting point, noting that Edward Snowden had endorsed it. Tails, designed to run anonymously from a USB drive or similar external device, was cited as another specialised option.
Inertia and the wider effect
Despite the consensus, there was no rush away from Windows and macOS. The argument made in 2018 was that even a modest rise in Linux desktop adoption could improve security for everyone, since losing market share is one of the few things that reliably pushes Microsoft and Apple to act.