Qubes is a security-oriented, open-source operating system for personal computers. It uses virtualization to implement security by compartmentalization and supports both Linux and Windows virtual environments. Qubes 3.0 introduces the Hypervisor Abstraction Layer (HAL), which renders Qubes independent of its underlying virtualization system.
The OS is the software which runs all the other programs on a computer. Some examples of popular OSes are Microsoft Windows, Mac OS X, Android, and iOS. Qubes is free and open-source software (FOSS). This means that everyone is free to use, copy, and change the software in any way. It also means that the source code is openly available so others can contribute to and audit it.
Why is OS security important?
Most people use an operating system like Windows or OS X on their desktop and laptop computers. These OSes are popular because they tend to be easy to use and usually come pre-installed on the computers people buy. However, they present problems when it comes to security. For example, you might open an innocent-looking email attachment or website, not realizing that you’re actually allowing malware (malicious software) to run on your computer. Depending on what kind of malware it is, it might do anything from showing you unwanted advertisements to logging your keystrokes to taking over your entire computer. This could jeopardize all the information stored on or accessed by this computer, such as health records, confidential communications, or thoughts written in a private journal. Malware can also interfere with the activities you perform with your computer. For example, if you use your computer to conduct financial transactions, the malware might allow its creator to make fradulent transactions in your name.
Aren’t antivirus programs and firewalls enough?
Unfortunately, conventional security approaches like antivirus programs and (software and/or hardware) firewalls are no longer enough to keep out sophisticated attackers. For example, nowadays it’s common for malware creators to check to see if their malware is recognized by any popular antivirus programs. If it’s recognized, they scramble their code until it’s no longer recognizable by the antivirus programs, then send it out. The best antivirus programs will subsequently get updated once the antivirus programmers discover the new threat, but this usually occurs at least a few days after the new attacks start to appear in the wild. By then, it’s typically too late for those who have already been compromised. In addition, bugs are inevitably discovered in the common software we all use (such as our web browsers), and no antivirus program or firewall can prevent all of these bugs from being exploited.
How does Qubes provide security?
Qubes allows you to separate the various parts of your digital life into securely isolated virtual machines (VMs). A VM is basically a simulated computer with its own OS which runs as software on your physical computer. You can think of a VM as a computer within a computer. This allows you to have, for example, one VM for visiting untrusted websites and a different VM for doing online banking. This way, if your untrusted browsing VM get compromised by a malware-laden website, your online banking activities won’t be at risk. Similarly, if you’re concerned about risky email attachments, Qubes can make it so that every attachment gets opened in its own single-use, “disposable” VM.
In general, Qubes takes an approach called security by isolation, which in this context means keeping the things you do on your computer securely isolated in different VMs so that one VM getting compromised won’t affect the others. This allows you to do everything on a single physical computer without having to worry about one successful cyberattack taking down your entire digital life in one fell swoop.