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@ -3,33 +3,45 @@ title: Linux Overview
icon: simple/linux
description: Linux is an open-source, privacy-focused desktop operating system alternative, but not all distribitions are created equal.
---
It is often believed that [open-source](https://en.wikipedia.org/wiki/Open-source_software) software is inherently secure because the source code is available. There is an expectation that community verification occurs regularly; however, this isn’t always [the case](https://seirdy.one/posts/2022/02/02/floss-security/). It does depend on a number of factors, such as project activity, developer experience, level of rigor applied to [code reviews](https://en.wikipedia.org/wiki/Code_review), and how often attention is given to specific parts of the [codebase](https://en.wikipedia.org/wiki/Codebase) that may go untouched for years.
**Linux** is an open-source, privacy-focused desktop operating system alternative. In the face of pervasive telemetry and other privacy-encroaching technologies in mainstream operating systems, Linux desktop has remained the clear choice for people looking for total control over their computers from the ground up.
At the moment, desktop Linux does have some areas that could be better improved when compared to their proprietary counterparts, e.g.:
- A verified boot chain, like Apple’s [Secure Boot](https://support.apple.com/guide/security/startup-security-utility-secc7b34e5b5/web) (with [Secure Enclave](https://support.apple.com/guide/security/secure-enclave-sec59b0b31ff/1/web/1)), Android’s [Verified Boot](https://source.android.com/security/verifiedboot), ChromeOS' [Verified boot](https://www.chromium.org/chromium-os/chromiumos-design-docs/security-overview/#verified-boot), or Microsoft Windows’s [boot process](https://docs.microsoft.com/en-us/windows/security/information-protection/secure-the-windows-10-boot-process) with [TPM](https://docs.microsoft.com/en-us/windows/security/information-protection/tpm/how-windows-uses-the-tpm). These features and hardware technologies can all help prevent persistent tampering by malware or [evil maid attacks](https://en.wikipedia.org/wiki/Evil_Maid_attack)
- A strong sandboxing solution such as that found in [macOS](https://developer.apple.com/library/archive/documentation/Security/Conceptual/AppSandboxDesignGuide/AboutAppSandbox/AboutAppSandbox.html), [ChromeOS](https://chromium.googlesource.com/chromiumos/docs/+/HEAD/sandboxing.md), and [Android](https://source.android.com/security/app-sandbox). Commonly used Linux sandboxing solutions such as [Flatpak](https://docs.flatpak.org/en/latest/sandbox-permissions.html) and [Firejail](https://firejail.wordpress.com/) still have a long way to go
- Strong [exploit mitigations](https://madaidans-insecurities.github.io/linux.html#exploit-mitigations)
Despite these drawbacks, desktop Linux distributions are great if you want to:
- Avoid telemetry that often comes with proprietary operating systems
- Maintain [software freedom](https://www.gnu.org/philosophy/free-sw.en.html#four-freedoms)
- Have privacy focused systems such as [Whonix](https://www.whonix.org) or [Tails](https://tails.boum.org/)
Our website generally uses the term “Linux” to describe desktop Linux distributions. Other operating systems which also use the Linux kernel such as ChromeOS, Android, and Qubes OS are not discussed here.
Our website generally uses the term “Linux” to describe **desktop** Linux distributions. Other operating systems which also use the Linux kernel such as ChromeOS, Android, and Qubes OS are not discussed on this page.
[Our Linux Recommendations :material-arrow-right-drop-circle:](../desktop.md){ .md-button }
## Privacy Notes
There are some notable privacy concerns with Linux which you should be aware of. Despite these drawbacks, desktop Linux distributions are still great for most people who want to:
- Avoid telemetry that often comes with proprietary operating systems
- Maintain [software freedom](https://www.gnu.org/philosophy/free-sw.en.html#four-freedoms)
- Use privacy focused systems such as [Whonix](https://www.whonix.org) or [Tails](https://tails.boum.org/)
### Open Source Security
It is a [common misconception](../basics/common-misconceptions.md#open-source-software-is-always-secure-or-proprietary-software-is-more-secure) that Linux and other open-source software is inherently secure simply because the source code is available. There is an expectation that community verification occurs regularly, but this isn’t always [the case](https://seirdy.one/posts/2022/02/02/floss-security/).
In reality, distro security depends on a number of factors, such as project activity, developer experience, the level of rigor applied to code reviews, and how often attention is given to specific parts of the codebase that may go untouched for years.
### Missing Security Features
At the moment, desktop Linux [falls behind alternatives](https://discussion.fedoraproject.org/t/fedora-strategy-2028-proposal-fedora-linux-is-as-secure-as-macos/46899/9) like macOS or Android when it comes to certain security features. We hope to see improvements in these areas in the future.
- **Verified boot** on Linux is not as robust as alternatives such as Apple’s [Secure Boot](https://support.apple.com/guide/security/secac71d5623/web) or Android’s [Verified Boot](https://source.android.com/security/verifiedboot). Verified boot prevents persistent tampering by malware and [evil maid attacks](https://en.wikipedia.org/wiki/Evil_Maid_attack), but is still largely [unavailable on even the most advanced distributions](https://discussion.fedoraproject.org/t/has-silverblue-achieved-verified-boot/27251/3).
- **Strong sandboxing** for apps on Linux is severely lacking, even with containerized apps like Flatpaks or sandboxing solutions like Firejail. Flatpak is the most promising sandboxing utility for Linux thus far, but is still deficient in many areas and allows for [unsafe defaults](https://flatkill.org/2020/) which allow most apps to trivially bypass their sandbox.
Additionally, Linux falls behind in implementing [exploit mitigations](https://madaidans-insecurities.github.io/linux.html#exploit-mitigations) which are now standard on other operating systems, such as Arbitrary Code Guard on Windows or Hardened Runtime on macOS. Also, most Linux programs and Linux itself are coded in memory-unsafe languages. Memory corruption bugs are responsible for the [majority of vulnerabilities](https://msrc.microsoft.com/blog/2019/07/a-proactive-approach-to-more-secure-code/) fixed and assigned a CVE. While this is also true for Windows and macOS, they are quickly making progress on adopting memory-safe languages—such as Rust and Swift, respectively—while there is no similar effort to rewrite Linux in a memory-safe language like Rust.
## Choosing your distribution
Not all Linux distributions are created equal. While our Linux recommendation page is not meant to be an authoritative source on which distribution you should use, there are a few things you should keep in mind when choosing which distribution to use.
Not all Linux distributions are created equal. Our [Linux recommendation page](../desktop.md) is not meant to be an authoritative source on which distribution you should use, but our recommendations *are* aligned with the following guidelines. These are a few things you should keep in mind when choosing a distribution:
### Release cycle
We highly recommend that you choose distributions which stay close to the stable upstream software releases, often referred to as rolling release distributions. This is because frozen release cycle distributions often don’t update package versions and fall behind on security updates.
For frozen distributions such as [Debian](https://www.debian.org/security/faq#handling), package maintainers are expected to backport patches to fix vulnerabilities rather than bump the software to the “next version” released by the upstream developer. Some security fixes [do not](https://arxiv.org/abs/2105.14565) receive a [CVE](https://en.wikipedia.org/wiki/Common_Vulnerabilities_and_Exposures) (particularly less popular software) at all and therefore do not make it into the distribution with this patching model. As a result minor security fixes are sometimes held back until the next major release.
For frozen distributions such as [Debian](https://www.debian.org/security/faq#handling), package maintainers are expected to backport patches to fix vulnerabilities rather than bump the software to the “next version” released by the upstream developer. Some security fixes [do not](https://arxiv.org/abs/2105.14565) receive a [CVE ID](https://en.wikipedia.org/wiki/Common_Vulnerabilities_and_Exposures) (particularly less popular software) at all and therefore do not make it into the distribution with this patching model. As a result minor security fixes are sometimes held back until the next major release.
We don’t believe holding packages back and applying interim patches is a good idea, as it diverges from the way the developer might have intended the software to work. [Richard Brown](https://rootco.de/aboutme/) has a presentation about this:
@ -53,28 +65,28 @@ The Atomic update method is used for immutable distributions like Silverblue, Tu
### “Security-focused” distributions
There is often some confusion between “security-focused” distributions and “pentesting” distributions. A quick search for “the most secure Linux distribution” will often give results like Kali Linux, Black Arch and Parrot OS. These distributions are offensive penetration testing distributions that bundle tools for testing other systems. They don’t include any “extra security” or defensive mitigations intended for regular use.
There is often some confusion between “security-focused” distributions and “pentesting” distributions. A quick search for “the most secure Linux distribution” will often give results like Kali Linux, Black Arch, or Parrot OS. These distributions are offensive penetration testing distributions that bundle tools for testing other systems. They don’t include any “extra security” or defensive mitigations intended for regular use.
### Arch-based distributions
Arch based distributions are not recommended for those new to Linux, (regardless of distribution) as they require regular [system maintenance](https://wiki.archlinux.org/title/System_maintenance). Arch does not have an distribution update mechanism for the underlying software choices. As a result you have to stay aware with current trends and adopt technologies as they supersede older practices on your own.
Arch and Arch-based distributions are not recommended for those new to Linux (regardless of distribution) as they require regular [system maintenance](https://wiki.archlinux.org/title/System_maintenance). Arch does not have a distribution update mechanism for the underlying software choices. As a result you have to stay aware with current trends and adopt technologies as they supersede older practices on your own.
For a secure system, you are also expected to have sufficient Linux knowledge to properly set up security for their system such as adopting a [mandatory access control](https://en.wikipedia.org/wiki/Mandatory_access_control) system, setting up [kernel module](https://en.wikipedia.org/wiki/Loadable_kernel_module#Security) blacklists, hardening boot parameters, manipulating [sysctl](https://en.wikipedia.org/wiki/Sysctl) parameters, and knowing what components they need such as [Polkit](https://en.wikipedia.org/wiki/Polkit).
Anyone using the [Arch User Repository (AUR)](https://wiki.archlinux.org/title/Arch_User_Repository), **must** be comfortable in auditing PKGBUILDs that they install from that service. AUR packages are community-produced content and are not vetted in any way, and therefore are vulnerable to software supply chain attacks, which has in fact happened [in the past](https://www.bleepingcomputer.com/news/security/malware-found-in-arch-linux-aur-package-repository/). AUR should always be used sparingly and often there is a lot of bad advice on various pages which direct people to blindly use [AUR helpers](https://wiki.archlinux.org/title/AUR_helpers) without sufficient warning. Similar warnings apply to use third-party Personal Package Archives (PPAs) on Debian based distributions or Community Projects (COPR) on Fedora.
Anyone using the [Arch User Repository (AUR)](https://wiki.archlinux.org/title/Arch_User_Repository) **must** be comfortable auditing PKGBUILDs that they download from that service. AUR packages are community-produced content and are not vetted in any way, and therefore are vulnerable to software supply chain attacks, which has in fact happened [in the past](https://www.bleepingcomputer.com/news/security/malware-found-in-arch-linux-aur-package-repository/).
If you are experienced with Linux and wish to use an Arch-based distribution, we only recommend mainline Arch Linux, not any of its derivatives. We recommend against these two Arch derivatives specifically:
The AUR should always be used sparingly, and often there is a lot of bad advice on various pages which direct people to blindly use [AUR helpers](https://wiki.archlinux.org/title/AUR_helpers) without sufficient warning. Similar warnings apply to use third-party Personal Package Archives (PPAs) on Debian based distributions or Community Projects (COPR) on Fedora.
If you are experienced with Linux and wish to use an Arch-based distribution, we generally recommend mainline Arch Linux over any of its derivatives.
Additionally, we recommend **against** these two Arch derivatives specifically:
- **Manjaro**: This distribution holds packages back for 2 weeks to make sure that their own changes don’t break, not to make sure that upstream is stable. When AUR packages are used, they are often built against the latest [libraries](https://en.wikipedia.org/wiki/Library_(computing)) from Arch’s repositories.
- **Garuda**: They use [Chaotic-AUR](https://aur.chaotic.cx/) which automatically and blindly compiles packages from the AUR. There is no verification process to make sure that the AUR packages don’t suffer from supply chain attacks.
### Kicksecure
While we strongly recommend against using outdated distributions like Debian, there is a Debian based operating system that has been hardened to be much more secure than typical Linux distributions: [Kicksecure](https://www.kicksecure.com/). Kicksecure, in oversimplified terms, is a set of scripts, configurations, and packages that substantially reduce the attack surface of Debian. It covers a lot of privacy and hardening recommendations by default.
### Linux-libre kernel and “Libre” distributions
We strongly recommend **against** using the Linux-libre kernel, since it [removes security mitigations](https://www.phoronix.com/news/GNU-Linux-Libre-5.7-Released) and [suppresses kernel warnings](https://news.ycombinator.com/item?id=29674846) about vulnerable microcode for ideological reasons.
We recommend **against** using the Linux-libre kernel, since it [removes security mitigations](https://www.phoronix.com/news/GNU-Linux-Libre-5.7-Released) and [suppresses kernel warnings](https://news.ycombinator.com/item?id=29674846) about vulnerable microcode.
## General Recommendations
@ -86,11 +98,13 @@ Most Linux distributions have an option within its installer for enabling [LUKS]
### Swap
Consider using [ZRAM](https://wiki.archlinux.org/title/Zram#Using_zram-generator) or [encrypted swap](https://wiki.archlinux.org/title/Dm-crypt/Swap_encryption) instead of unencrypted swap to avoid potential security issues with sensitive data being pushed to [swap space](https://en.wikipedia.org/wiki/Memory_paging). Fedora based distributions [use ZRAM by default](https://fedoraproject.org/wiki/Changes/SwapOnZRAM).
Consider using [ZRAM](https://wiki.archlinux.org/title/Zram#Using_zram-generator) instead of a traditional swap file or partition to avoid writing potentially sensitive memory data to persistent storage (and improve performance). Fedora-based distributions [use ZRAM by default](https://fedoraproject.org/wiki/Changes/SwapOnZRAM).
If you require suspend-to-disk (hibernation) functionality, you will still need to use a traditional swap file or partition. Make sure that any swap space you do have on a persistent storage device is [encrypted](https://wiki.archlinux.org/title/Dm-crypt/Swap_encryption) at a minimum to mitigate some of these threats.
### Wayland
We recommend using a desktop environment that supports the [Wayland](https://en.wikipedia.org/wiki/Wayland_(display_server_protocol)) display protocol as it was developed with security [in mind](https://lwn.net/Articles/589147/). Its predecessor, [X11](https://en.wikipedia.org/wiki/X_Window_System), does not support GUI isolation, allowing all windows to [record screen, log and inject inputs in other windows](https://blog.invisiblethings.org/2011/04/23/linux-security-circus-on-gui-isolation.html), making any attempt at sandboxing futile. While there are options to do nested X11 such as [Xpra](https://en.wikipedia.org/wiki/Xpra) or [Xephyr](https://en.wikipedia.org/wiki/Xephyr), they often come with negative performance consequences and are not convenient to set up and are not preferable over Wayland.
We recommend using a desktop environment that supports the [Wayland](https://en.wikipedia.org/wiki/Wayland_(display_server_protocol)) display protocol, as it was developed with security [in mind](https://lwn.net/Articles/589147/). Its predecessor ([X11](https://en.wikipedia.org/wiki/X_Window_System)) does not support GUI isolation, which allows any window to [record, log, and inject inputs in other windows](https://blog.invisiblethings.org/2011/04/23/linux-security-circus-on-gui-isolation.html), making any attempt at sandboxing futile. While there are options to do nested X11 such as [Xpra](https://en.wikipedia.org/wiki/Xpra) or [Xephyr](https://en.wikipedia.org/wiki/Xephyr), they often come with negative performance consequences, and are neither convenient to set up nor preferable over Wayland.
Fortunately, common environments such as [GNOME](https://www.gnome.org), [KDE](https://kde.org), and the window manager [Sway](https://swaywm.org) have support for Wayland. Some distributions like Fedora and Tumbleweed use it by default, and some others may do so in the future as X11 is in [hard maintenance mode](https://www.phoronix.com/news/X.Org-Maintenance-Mode-Quickly). If you’re using one of those environments it is as easy as selecting the “Wayland” session at the desktop display manager ([GDM](https://en.wikipedia.org/wiki/GNOME_Display_Manager), [SDDM](https://en.wikipedia.org/wiki/Simple_Desktop_Display_Manager)).
@ -98,15 +112,15 @@ We recommend **against** using desktop environments or window managers that do n
### Proprietary Firmware (Microcode Updates)
Linux distributions such as those which are [Linux-libre](https://en.wikipedia.org/wiki/Linux-libre) or DIY (Arch Linux) don’t come with the proprietary [microcode](https://en.wikipedia.org/wiki/Microcode) updates that often patch vulnerabilities. Some notable examples of these vulnerabilities include [Spectre](https://en.wikipedia.org/wiki/Spectre_(security_vulnerability)), [Meltdown](https://en.wikipedia.org/wiki/Meltdown_(security_vulnerability)), [SSB](https://en.wikipedia.org/wiki/Speculative_Store_Bypass), [Foreshadow](https://en.wikipedia.org/wiki/Foreshadow), [MDS](https://en.wikipedia.org/wiki/Microarchitectural_Data_Sampling), [SWAPGS](https://en.wikipedia.org/wiki/SWAPGS_(security_vulnerability)), and other [hardware vulnerabilities](https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/index.html).
Some Linux distributions (such as [Linux-libre](https://en.wikipedia.org/wiki/Linux-libre)-based or DIY distros) don’t come with the proprietary [microcode](https://en.wikipedia.org/wiki/Microcode) updates which patch critical security vulnerabilities. Some notable examples of these vulnerabilities include [Spectre](https://en.wikipedia.org/wiki/Spectre_(security_vulnerability)), [Meltdown](https://en.wikipedia.org/wiki/Meltdown_(security_vulnerability)), [SSB](https://en.wikipedia.org/wiki/Speculative_Store_Bypass), [Foreshadow](https://en.wikipedia.org/wiki/Foreshadow), [MDS](https://en.wikipedia.org/wiki/Microarchitectural_Data_Sampling), [SWAPGS](https://en.wikipedia.org/wiki/SWAPGS_(security_vulnerability)), and other [hardware vulnerabilities](https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/index.html).
We **highly recommend** that you install the microcode updates, as your CPU is already running the proprietary microcode from the factory. Fedora and openSUSE both have the microcode updates applied by default.
We **highly recommend** that you install microcode updates, as they contain important security patches for the CPU which can not be fully mitigated in software alone. Fedora and openSUSE both have the microcode updates applied by default.
### Updates
Most Linux distributions will automatically install updates or remind you to do so. It is important to keep your OS up to date so that your software is patched when a vulnerability is found.
Some distributions (particularly those aimed at advanced users) are more barebones and expect you to do things yourself (e.g. Arch or Debian). These will require running the "package manager" (`apt`, `pacman`, `dnf`, etc.) manually in order to receive important security updates.
Some distributions (particularly those aimed at advanced users) are more bare bones and expect you to do things yourself (e.g. Arch or Debian). These will require running the "package manager" (`apt`, `pacman`, `dnf`, etc.) manually in order to receive important security updates.
Additionally, some distributions will not download firmware updates automatically. For that you will need to install [`fwupd`](https://wiki.archlinux.org/title/Fwupd).
@ -114,7 +128,7 @@ Additionally, some distributions will not download firmware updates automaticall
### MAC Address Randomization
Many desktop Linux distributions (Fedora, openSUSE, etc.) will come with [NetworkManager](https://en.wikipedia.org/wiki/NetworkManager), to configure Ethernet and Wi-Fi settings.
Many desktop Linux distributions (Fedora, openSUSE, etc.) come with [NetworkManager](https://en.wikipedia.org/wiki/NetworkManager) to configure Ethernet and Wi-Fi settings.
It is possible to [randomize](https://fedoramagazine.org/randomize-mac-address-nm/) the [MAC address](https://en.wikipedia.org/wiki/MAC_address) when using NetworkManager. This provides a bit more privacy on Wi-Fi networks as it makes it harder to track specific devices on the network you’re connected to. It does [**not**](https://papers.mathyvanhoef.com/wisec2016.pdf) make you anonymous.
@ -122,7 +136,7 @@ We recommend changing the setting to **random** instead of **stable**, as sugges
If you are using [systemd-networkd](https://en.wikipedia.org/wiki/Systemd#Ancillary_components), you will need to set [`MACAddressPolicy=random`](https://www.freedesktop.org/software/systemd/man/systemd.link.html#MACAddressPolicy=) which will enable [RFC 7844 (Anonymity Profiles for DHCP Clients)](https://www.freedesktop.org/software/systemd/man/systemd.network.html#Anonymize=).
There isn’t many points in randomizing the MAC address for Ethernet connections as a system administrator can find you by looking at the port you are using on the [network switch](https://en.wikipedia.org/wiki/Network_switch). Randomizing Wi-Fi MAC addresses depends on support from the Wi-Fi’s firmware.
MAC address randomization is primarily beneficial for Wi-Fi connections. For Ethernet connections, randomizing your MAC address provides little (if any) benefit, because a network administrator can trivially identify your device by other means (such as inspecting the port you are connected to on the network switch). Randomizing Wi-Fi MAC addresses depends on support from the Wi-Fi’s firmware.
### Other Identifiers