Ubuntu Linux operating system is the most secure end-user operating system currently available, according to research done by the Communications-Electronics Security Group (CESG). The CESG is part of the British Government Communication Headquarters (GCHQ), and while none of the OSes is completely secure, Ubuntu Linux 12.04 was rated the highest.
Each OS was rated on criteria such as Virtual Private Network (VPN) support, disk encryption, authentication, malicious code detection and prevention, incident response, and device update policy, among other categories. Ubuntu's built-in VPN struggled to meet the strict criteria set by the CESG, though hopes its own VPN will be supported with Ubuntu 14.04, scheduled for an April launch date.
During the analysis, researchers took a look at the following operating systems - for both desktop and mobile devices - Android 4.2, Android 4.2 on Samsung devices, Apple iOS 6, Google Chrome OS 26, BlackBerry 10.1, Ubuntu 12.04, Windows 7 and 8, Windows 8 RT, and Windows Phone 8.