Install

Table of Contents

• Pre-install
• Terms of Use
• Installation
  • Secureblue ISO (Desktop)
    • ISO Verification
  • Ignition (CoreOS)
• Post-install

Pre-install

Before installation, the following checks are recommended:

• Ensure SecureBoot is enabled.
• Ensure your BIOS is up-to-date by checking its manufacturer’s website.
• Disable booting from USB (some manufacturers allow firmware changes from live systems).
• Set a BIOS password to prevent tampering.

Terms of Use

secureblue includes a combination of software packages, each under its own licensing terms. The license of secureblue is the Apache License 2.0. The license of secureblue does not supersede the licenses of upstream code and content contained in secureblue images. By downloading secureblue you agree to the license terms of its use.

Copyright 2024-2025 The Secureblue Authors

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this software except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

Installation

To install secureblue, you will use one of the following processes. Consult the table below for the right starting point for your use case. For more details on the available images, have a look at the list of available images before proceeding.

Things to remember during installation:

• Select the option to encrypt the drive you’re installing to.
• Use a strong password when prompted.
• Select wheel group membership for your user when prompted.

Secureblue ISO (Desktop)

ISO Verification

You should now have the ISO with its corresponding CHECKSUM file, the keyring file, and if you opted to use a torrent, the torrent file with its corresponding CHECKSUM file. Use following commands to verify the ISO (where ${IMAGE_NAME} corresponds to the filename of the ISO you downloaded).

For all users

First command:

gpgv --keyring ./secureblue-keyring.gpg "${IMAGE_NAME}.iso-CHECKSUM"

Expected output:

gpgv: Signature made Wed 04 Jun 2025 12:49:39 AM PDT
gpgv:                using EDDSA key 26B4463ED8F313BC7E3FBDF9D9223AF0F47B3E41
gpgv: Good signature from "secureblueadmin <secureblueadmin@proton.me>"

Second command:

sha256sum -c "${IMAGE_NAME}.iso-CHECKSUM"

Expected output:

IMAGE_NAME.iso: OK
sha256sum: WARNING: 8 lines are improperly formatted

For torrent users

First command:

gpgv --keyring ./secureblue-keyring.gpg "${IMAGE_NAME}.iso.torrent-CHECKSUM"

Expected output:

gpgv: Signature made Wed 04 Jun 2025 12:49:39 AM PDT
gpgv:                using EDDSA key 26B4463ED8F313BC7E3FBDF9D9223AF0F47B3E41
gpgv: Good signature from "secureblueadmin <secureblueadmin@proton.me>"

Second command:

sha256sum -c "${IMAGE_NAME}.iso.torrent-CHECKSUM"

Expected output:

IMAGE_NAME.iso.torrent: OK
sha256sum: WARNING: 8 lines are improperly formatted

Ignition (Server)

Follow the Fedora CoreOS docs, Ignition docs, and Butane docs to configure initialization for your CoreOS instance(s).

You can use our example.butane as a starting point.

Post-install

• Essential
  • Subscribe to secureblue release notifications
  • Enroll SecureBoot key
  • Validation
  • Read the FAQ
• Recommended
  • Kernel argument tuning
  • Setup USBGuard
  • Create a separate wheel account for admin purposes
  • Setup system DNS
  • Toggle MAC address randomization
  • Bash environment lockdown
  • LUKS Hardware Unlock
  • Flatpak Permissions Tuning
  • Trivalent Flags

Subscribe to secureblue release notifications

Subscribing to release notifications is documented here.

Enroll SecureBoot key

The secureblue Secure Boot key should automatically enroll after installation, with the MOK password “secureblue”. If this fails or doesn’t appear for whatever reason, you can manually enroll the key with the command below.

ujust enroll-secureblue-secure-boot-key

Validation

To validate your secureblue setup, run:

ujust audit-secureblue

Read the FAQ

Lots of important stuff is covered in the FAQ. If you’re having an issue, it’s probably covered there already. AppImage toggles, GNOME extension toggles, Xwayland toggles, etc.

Kernel argument tuning

A stable set of kernel arguments is preinstalled with secureblue. However, it is recommended that you consult our Kargs article for guidance on tuning Kargs based on your use case.

Flatpak Permissions Tuning

Consult our Flatpak article for guidance on tuning Flatpak permissions.

Setup USBGuard

This will generate a policy based on your currently attached USB devices and block all others, then enable usbguard.

ujust setup-usbguard

Create a separate wheel account for admin purposes

Creating a dedicated wheel user and removing wheel from your primary user helps prevent certain privilege escalation attack vectors and password sniffing. We log in as admin to do the final step of removing the user account's wheel privileges in order to make the operation of removing those privileges depend on having access to your admin account, and the admin account functioning correctly first.’ You don't need to log in using your wheel user to use it for privileged operations. When logged in as your non-wheel user, Polkit will prompt you to authenticate as your wheel user as needed, or when requested by calling run0.

1. run0
2. adduser admin
3. usermod -aG wheel admin
4. passwd admin
5. exit
6. reboot
7. Log in as admin
8. run0
9. gpasswd -d {your username here} wheel
10. reboot

Configure system DNS

The command below will interactively setup system DNS resolution for systemd-resolved (and optionally set the resolver for Trivalent via management policy). If you intend to use a VPN, use the system default state (network provided resolver). This will ensure your system uses the VPN provided DNS resolver to prevent DNS leaks. ESPECIALLY avoid setting the browser DNS policy in this case.

ujust dns-selector

Toggle MAC address randomization

Toggle system-wide MAC address randomization in NetworkManager between random and permanent using the command below. Disabling MAC randomization can help with network compatibility issues, especially in enterprise or captive portal environments. Enabling it improves privacy by preventing tracking across networks.

ujust toggle-mac-randomization

Bash environment lockdown

To mitigate LD_PRELOAD attacks, run:

ujust toggle-bash-environment-lockdown

LUKS Hardware-Unlock

There are two options available for hardware-based unlocking. You can either enroll FIDO2 or TPM2 for your LUKS volume. FIDO2 enrollment is preferable if you own a hardware security key. It's recommended that you choose only one of these, and not both at the same time.

LUKS FIDO2 Unlock

To enable FIDO2 LUKS unlocking with your FIDO2 security key, run:

ujust setup-luks-fido2-unlock

LUKS TPM2 Unlock

To enable TPM2 LUKS unlocking, run:

ujust setup-luks-tpm-unlock

Type Y when asked if you want to set a PIN.

Trivalent Flags

The included Trivalent browser has some additional settings in chrome://flags you may want to set for additional hardening and convenience (can cause functionality issues in some cases).

You can read about these settings in the Trivalent post-install instructions.