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---
title: Android Overview
icon: simple/android
---
Android is a secure operating system that has strong [app sandboxing](https://source.android.com/security/app-sandbox), [Verified Boot](https://source.android.com/security/verifiedboot) (AVB), and a robust [permission](https://developer.android.com/guide/topics/permissions/overview) control system.
## Choosing an Android Distribution
When you buy an Android phone, the device's default operating system often comes with invasive integration with apps and services that are not part of the [Android Open-Source Project](https://source.android.com/). An example of such is Google Play Services, which has irrevocable privileges to access your files, contacts storage, call logs, SMS messages, location, camera, microphone, hardware identifiers, and so on. These apps and services increase the attack surface of your device and are the source of various privacy concerns with Android.
This problem could be solved by using a custom Android distribution that does not come with such invasive integration. Unfortunately, many custom Android distributions often violate the Android security model by not supporting critical security features such as AVB, rollback protection, firmware updates, and so on. Some distributions also ship [`userdebug`](https://source.android.com/setup/build/building#choose-a-target) builds which expose root via [ADB](https://developer.android.com/studio/command-line/adb) and require [more permissive](https://github.com/LineageOS/android_system_sepolicy/search?q=userdebug&type=code) SELinux policies to accommodate debugging features, resulting in a further increased attack surface and weakened security model.
Ideally, when choosing a custom Android distribution, you should make sure that it upholds the Android security model. At the very least, the distribution should have production builds, support for AVB, rollback protection, timely firmware and operating system updates, and SELinux in [enforcing mode](https://source.android.com/security/selinux/concepts#enforcement_levels). All of our recommended Android distributions satisfy these criteria.
[Our Android System Recommendations :material-arrow-right-drop-circle:](../android.md){ .md-button }
## Avoid Rooting
[Rooting](https://en.wikipedia.org/wiki/Rooting_(Android)) Android phones can decrease security significantly as it weakens the complete [Android security model](https://en.wikipedia.org/wiki/Android_(operating_system)#Security_and_privacy). This can decrease privacy should there be an exploit that is assisted by the decreased security. Common rooting methods involve directly tampering with the boot partition, making it impossible to perform successful Verified Boot. Apps that require root will also modify the system partition meaning that Verified Boot would have to remain disabled. Having root exposed directly in the user interface also increases the [attack surface](https://en.wikipedia.org/wiki/Attack_surface) of your device and may assist in [privilege escalation](https://en.wikipedia.org/wiki/Privilege_escalation) vulnerabilities and SELinux policy bypasses.
Adblockers, which modify the [hosts file](https://en.wikipedia.org/wiki/Hosts_(file)) (AdAway) and firewalls (AFWall+) which require root access persistently are dangerous and should not be used. They are also not the correct way to solve their intended purposes. For Adblocking we suggest encrypted [DNS](../dns.md) or [VPN](../vpn.md) server blocking solutions instead. RethinkDNS, TrackerControl and AdAway in non-root mode will take up the VPN slot (by using a local loopback VPN) preventing you from using privacy enhancing services such as Orbot or a real VPN server.
AFWall+ works based on the [packet filtering](https://en.wikipedia.org/wiki/Firewall_(computing)#Packet_filter) approach and may be bypassable in some situations.
We do not believe that the security sacrifices made by rooting a phone are worth the questionable privacy benefits of those apps.
## Verified Boot
[Verified Boot](https://source.android.com/security/verifiedboot) is an important part of the Android security model. It provides protection against [evil maid](https://en.wikipedia.org/wiki/Evil_maid_attack) attacks, malware persistence, and ensures security updates cannot be downgraded with [rollback protection](https://source.android.com/security/verifiedboot/verified-boot#rollback-protection).
Android 10 and above has moved away from full-disk encryption to more flexible [file-based encryption](https://source.android.com/security/encryption/file-based). Your data is encrypted using unique encryption keys, and the operating system files are left unencrypted.
Verified Boot ensures the integrity of the operating system files, thereby preventing an adversary with physical access from tampering or installing malware on the device. In the unlikely case that malware is able to exploit other parts of the system and gain higher privileged access, Verified Boot will prevent and revert changes to the system partition upon rebooting the device.
Unfortunately, OEMs are only obliged to support Verified Boot on their stock Android distribution. Only a few OEMs such as Google support custom AVB key enrollment on their devices. Additionally, some AOSP derivatives such as LineageOS or /e/ OS do not support Verified Boot even on hardware with Verified Boot support for third-party operating systems. We recommend that you check for support **before** purchasing a new device. AOSP derivatives which do not support Verified Boot are **not** recommended.
Many OEMs also have broken implementation of Verified Boot that you have to be aware of beyond their marketing. For example, the Fairphone 3 and 4 are not secure by default, as the [stock bootloader trusts the public AVB signing key](https://forum.fairphone.com/t/bootloader-avb-keys-used-in-roms-for-fairphone-3-4/83448/11). This breaks verified boot on a stock Fairphone device, as the system will boot alternative Android operating systems such (such as /e/) [without any warning](https://source.android.com/security/verifiedboot/boot-flow#locked-devices-with-custom-root-of-trust) about custom operating system usage.
## Firmware Updates
Firmware updates are critical for maintaining security and without them your device cannot be secure. OEMs have support agreements with their partners to provide the closed-source components for a limited support period. These are detailed in the monthly [Android Security Bulletins](https://source.android.com/security/bulletin).
As the components of the phone, such as the processor and radio technologies rely on closed-source components, the updates must be provided by the respective manufacturers. Therefore, it is important that you purchase a device within an active support cycle. [Qualcomm](https://www.qualcomm.com/news/releases/2020/12/16/qualcomm-and-google-announce-collaboration-extend-android-os-support-and) and [Samsung](https://news.samsung.com/us/samsung-galaxy-security-extending-updates-knox/) support their devices for 4 years, while cheaper products often have shorter support cycles. With the introduction of the [Pixel 6](https://support.google.com/pixelphone/answer/4457705), Google now makes their own SoC and they will provide a minimum of 5 years of support.
EOL devices which are no longer supported by the SoC manufacturer cannot receive firmware updates from OEM vendors or after market Android distributors. This means that security issues with those devices will remain unfixed.
Fairphone, for example, markets their devices as receiving 6 years of support. However, the SoC (Qualcomm Snapdragon 750G on the Fairphone 4) has a considerably shorter EOL date. This means that firmware security updates from Qualcomm for the Fairphone 4 will end in September 2023, regardless of whether Fairphone continues to release software security updates.
## Android Versions
It's important to not use an [end-of-life](https://endoflife.date/android) version of Android. Newer versions of Android not only receive security updates for the operating system but also important privacy enhancing updates too. For example, [prior to Android 10](https://developer.android.com/about/versions/10/privacy/changes), any apps with the [`READ_PHONE_STATE`](https://developer.android.com/reference/android/Manifest.permission#READ_PHONE_STATE) permission could access sensitive and unique serial numbers of your phone such as [IMEI](https://en.wikipedia.org/wiki/International_Mobile_Equipment_Identity), [MEID](https://en.wikipedia.org/wiki/Mobile_equipment_identifier), your SIM card's [IMSI](https://en.wikipedia.org/wiki/International_mobile_subscriber_identity), whereas now they must be system apps to do so. System apps are only provided by the OEM or Android distribution.
## Android Permissions
[Permissions on Android](https://developer.android.com/guide/topics/permissions/overview) grant you control over what apps are allowed to access. Google regularly makes [improvements](https://developer.android.com/about/versions/11/privacy/permissions) on the permission system in each successive version. All apps you install are strictly [sandboxed](https://source.android.com/security/app-sandbox), therefore, there is no need to install any antivirus apps. A smartphone with the latest version of Android will always be more secure than an old smartphone with an antivirus that you have paid for. It's better not to pay for antivirus software and to save money to buy a new smartphone such as a Google Pixel.
Should you want to run an app that you're unsure about, consider using a user or work profile.
## Media Access
Quite a few applications allows you to "share" a file with them for media upload. If you want to, for example, tweet a picture to Twitter, do not grant Twitter access to your "media and photos", because it will have access to all of your pictures then. Instead, go to your file manager (documentsUI), hold onto the picture, then share it with Twitter.
## User Profiles
Multiple user profiles can be found in **Settings** → **System** → **Multiple users** and are the simplest way to isolate in Android.
With user profiles, you can impose restrictions on a specific profile, such as: making calls, using SMS, or installing apps on the device. Each profile is encrypted using its own encryption key and cannot access the data of any other profiles. Even the device owner cannot view the data of other profiles without knowing their password. Multiple user profiles are a more secure method of isolation.
## Work Profile
[Work Profiles](https://support.google.com/work/android/answer/6191949) are another way to isolate individual apps and may be more convenient than separate user profiles.
A **device controller** app such as [Shelter](#recommended-apps) is required to create a Work Profile without an enterprise MDM, unless you're using a custom Android OS which includes one.
The work profile is dependent on a device controller to function. Features such as *File Shuttle* and *contact search blocking* or any kind of isolation features must be implemented by the controller. You must also fully trust the device controller app, as it has full access to your data inside of the work profile.
This method is generally less secure than a secondary user profile; however, it does allow you the convenience of running apps in both the work and personal profiles simultaneously.
## VPN Killswitch
Android 7 and above supports a VPN killswitch and it is available without the need to install third-party apps. This feature can prevent leaks if the VPN is disconnected. It can be found in :gear: **Settings** → **Network & internet** → **VPN** → :gear: → **Block connections without VPN**.
## Global Toggles
Modern Android devices have global toggles for disabling Bluetooth and location services. Android 12 introduced toggles for the camera and microphone. When not in use, we recommend disabling these features. Apps cannot use disabled features (even if granted individual permission) until re-enabled.
## Google
If you are using a device with Google services, either your stock operating system or an operating system that safely sandboxes Google Play Services like GrapheneOS, there are a number of additional changes you can make to improve your privacy. We still recommend avoiding Google services entirely, or limiting Google Play services to a specific user/work profile by combining a device controller like *Shelter* with GrapheneOS's Sandboxed Google Play.
### Advanced Protection Program
If you have a Google account we suggest enrolling in the [Advanced Protection Program](https://landing.google.com/advancedprotection/). It is available at no cost to anyone with two or more hardware security keys with [FIDO](../basics/multi-factor-authentication.md#fido-fast-identity-online) support.
The Advanced Protection Program provides enhanced threat monitoring and enables:
- Stricter two factor authentication; e.g. that [FIDO](../basics/multi-factor-authentication.md#fido-fast-identity-online) **must** be used and disallows the use of [SMS OTPs](../basics/multi-factor-authentication.md#sms-or-email-mfa), [TOTP](../basics/multi-factor-authentication.md#time-based-one-time-password-totp) and [OAuth](https://en.wikipedia.org/wiki/OAuth)
- Only Google and verified third-party apps can access account data
- Scanning of incoming emails on Gmail accounts for [phishing](https://en.wikipedia.org/wiki/Phishing#Email_phishing) attempts
- Stricter [safe browser scanning](https://www.google.com/chrome/privacy/whitepaper.html#malware) with Google Chrome
- Stricter recovery process for accounts with lost credentials
If you use non-sandboxed Google Play Services (common on stock operating systems), the Advanced Protection Program also comes with [additional benefits](https://support.google.com/accounts/answer/9764949?hl=en) such as:
- Not allowing app installation outside of the Google Play Store, the OS vendor's app store, or via [`adb`](https://en.wikipedia.org/wiki/Android_Debug_Bridge)
- Mandatory automatic device scanning with [Play Protect](https://support.google.com/googleplay/answer/2812853?hl=en#zippy=%2Chow-malware-protection-works%2Chow-privacy-alerts-work)
- Warning you about unverified applications
### Google Play System Updates
In the past, Android security updates had to be shipped by the operating system vendor. Android has become more modular beginning with Android 10, and Google can push security updates for **some** system components via the privileged Play Services.
If you have an EOL device shipped with Android 10 or above and are unable to run any of our recommended operating systems on your device, you are likely going to be better off sticking with your OEM Android installation (as opposed to an operating system not listed here such as LineageOS or /e/ OS). This will allow you to receive **some** security fixes from Google, while not violating the Android security model by using an insecure Android derivative and increasing your attack surface. We would still recommend upgrading to a supported device as soon as possible.
### Advertising ID
All devices with Google Play Services installed automatically generate an [advertising ID](https://support.google.com/googleplay/android-developer/answer/6048248?hl=en) used for targeted advertising. Disable this feature to limit the data collected about you.
On Android distributions with [Sandboxed Google Play](https://grapheneos.org/usage#sandboxed-google-play), go to :gear: **Settings** → **Apps** → **Sandboxed Google Play** → **Google Settings** → **Ads**, and select *Delete advertising ID*.
On Android distributions with privileged Google Play Services (such as stock OSes), the setting may be in one of several locations. Check
- :gear: **Settings** → **Google** → **Ads**
- :gear: **Settings** → **Privacy** → **Ads**
You will either be given the option to delete your advertising ID or to *Opt out of interest-based ads*, this varies between OEM distributions of Android. If presented with the option to delete the advertising ID that is preferred. If not, then make sure to opt out and reset your advertising ID.
### SafetyNet and Play Integrity API
[SafetyNet](https://developer.android.com/training/safetynet/attestation) and the [Play Integrity APIs](https://developer.android.com/google/play/integrity) are generally used for [banking apps](https://grapheneos.org/usage#banking-apps). Many banking apps will work fine in GrapheneOS with sandboxed Play services, however some non-financial apps have their own crude anti-tampering mechanisms which might fail. GrapheneOS passes the `basicIntegrity` check, but not the certification check `ctsProfileMatch`. Devices with Android 8 or later have hardware attestation support which cannot be bypassed without leaked keys or serious vulnerabilities.
As for Google Wallet, we don't recommend this due to their [privacy policy](https://payments.google.com/payments/apis-secure/get_legal_document?ldo=0&ldt=privacynotice&ldl=en), which states you must opt-out if you don't want your credit rating and personal information shared with affiliate marketing services.

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---
title: Linux Overview
icon: simple/linux
---
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 rigour 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.
At the moment, desktop GNU/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 GNU/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 GNU/Linux distributions. Other operating systems which also use the Linux kernel such as ChromeOS, Android, and Qubes OS are not discussed here.
[Our Linux Recommendations :material-arrow-right-drop-circle:](../linux-desktop.md){ .md-button }
## 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.
### 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.
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:
<div class="yt-embed">
<iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/i8c0mg_mS7U" title="Regular Releases are Wrong, Roll for your life" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
</div>
### Traditional vs Atomic updates
Traditionally, Linux distributions update by sequentially updating the desired packages. Traditional updates such as those used in Fedora, Arch Linux, and Debian based distributions can be less reliable if an error occurs while updating.
Atomic updating distributions apply updates in full or not at all. Typically, transactional update systems are also atomic.
A transactional update system creates a snapshot that is made before and after an update is applied. If an update fails at any time (perhaps due to a power failure), the update can be easily rolled back to a “last known good state."
The Atomic update method is used for immutable distributions like Silverblue, Tumbleweed, and NixOS and can achieve reliability with this model. [Adam Šamalík](https://twitter.com/adsamalik) provided a presentation on how `rpm-ostree` works with Silverblue:
<div class="yt-embed">
<iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/-hpV5l-gJnQ" title="Let's try Fedora Silverblue — an immutable desktop OS! - Adam Šamalik" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
</div>
### “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.
### 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.
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.
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:
- **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/scan.php?page=news_item&px=GNU-Linux-Libre-5.7-Released) and [suppresses kernel warnings](https://news.ycombinator.com/item?id=29674846) about vulnerable microcode for ideological reasons.
## General Recommendations
### Drive Encryption
Most Linux distributions have an option within its installer for enabling [LUKS](../encryption.md#linux-unified-key-setup) FDE. If this option isn’t set at installation time, you will have to backup your data and re-install, as encryption is applied after [disk partitioning](https://en.wikipedia.org/wiki/Disk_partitioning), but before [file systems](https://en.wikipedia.org/wiki/File_system) are formatted. We also suggest securely erasing your storage device:
- [Secure Data Erasure :material-arrow-right-drop-circle:](https://blog.privacyguides.org/2022/05/25/secure-data-erasure/)
### Swap
Consider using [ZRAM](https://wiki.archlinux.org/title/Swap#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).
### Wayland
We recommend using a desktop environment that supports the [Wayland](https://en.wikipedia.org/wiki/Wayland_(display_server_protocol)) display protocol as it 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.
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/scan.php?page=news_item&px=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)).
We recommend **against** using desktop environments or window managers that do not have Wayland support, such as Cinnamon (default on Linux Mint), Pantheon (default on Elementary OS), MATE, Xfce, and i3.
### 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. 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.
## Privacy Tweaks
### 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.
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.
We recommend changing the setting to **random** instead of **stable**, as suggested in the [article](https://fedoramagazine.org/randomize-mac-address-nm/).
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.
### Other Identifiers
There are other system identifiers which you may wish to be careful about. You should give this some thought to see if it applies to your [threat model](../basics/threat-modeling.md):
- **Hostnames:** Your system's hostname is shared with the networks you connect to. You should avoid including identifying terms like your name or operating system in your hostname, instead sticking to generic terms or random strings.
- **Usernames:** Similarly, your username is used in a variety of ways across your system. Consider using generic terms like "user" rather than your actual name.
- **Machine ID:**: During installation a unique machine ID is generated and stored on your device. Consider [setting it to a generic ID](https://madaidans-insecurities.github.io/guides/linux-hardening.html#machine-id).
### System Counting
The Fedora Project [counts](https://fedoraproject.org/wiki/Changes/DNF_Better_Counting) how many unique systems access its mirrors by using a [`countme`](https://fedoraproject.org/wiki/Changes/DNF_Better_Counting#Detailed_Description) variable instead of a unique ID. Fedora does this to determine load and provision better servers for updates where necessary.
This [option](https://dnf.readthedocs.io/en/latest/conf_ref.html#options-for-both-main-and-repo) is currently off by default. We recommend adding `countme=false` to `/etc/dnf/dnf.conf` just in case it is enabled in the future. On systems that use `rpm-ostree` such as Silverblue, the countme option is disabled by masking the [rpm-ostree-countme](https://fedoramagazine.org/getting-better-at-counting-rpm-ostree-based-systems/) timer.
openSUSE also uses a [unique ID](https://en.opensuse.org/openSUSE:Statistics) to count systems, which can be disabled by deleting the `/var/lib/zypp/AnonymousUniqueId` file.