Security Onion: March 2026

Thursday, March 12, 2026

Security Onion 2.4.211 Is Now Available and Resolves Several Issues!

Last week, we released Security Onion 2.4.210:

https://blog.securityonion.net/2026/03/security-onion-24210-now-available-with.html

We found and fixed a few issues resulting in today's release of Security Onion 2.4.211:

https://docs.securityonion.net/en/2.4/release-notes.html

Known Issues

For a list of known issues, please see:

https://docs.securityonion.net/en/2.4/release-notes.html#known-issues

Existing 2.4 Installations

If you have an existing Security Onion 2.4 installation, you can update to the latest version using soup:

https://docs.securityonion.net/en/2.4/soup.html

Before updating your production deployment, we highly recommend testing the upgrade process on a test deployment that closely matches your production deployment if possible. This is especially important for releases that update components like Salt and Elastic.

New Installations

If this is your first time installing Security Onion 2.4, then we highly recommend starting with an IMPORT installation as shown at:

https://docs.securityonion.net/en/2.4/first-time-users.html

Once you’re comfortable with your IMPORT installation, then you can move on to more advanced installations as shown at:

https://docs.securityonion.net/en/2.4/architecture.html

Documentation

You can find our online documentation here:

https://docs.securityonion.net/en/2.4/

Documentation is always a work in progress. If you find documentation that needs to be updated, please let us know as described in the Feedback section below.

Questions, Problems, and Feedback

If you have any questions or problems relating to Security Onion 2.4, please use the 2.4 category at our Discussions site:

https://github.com/Security-Onion-Solutions/securityonion/discussions/categories/2-4

Security Onion Pro

We recently celebrated 10 years in business by announcing Security Onion Pro:

https://blog.securityonion.net/2024/07/celebrating-10-years-of-security-onion.html

Security Onion Pro includes many enterprise features that folks have been asking for:

Active Query Management
External API
Open ID Connect (OIDC)
Data at Rest Encryption
FIPS for the OS
DoD STIG for the OS
External Notifications in SOC
Time Tracking inside of Cases
Guaranteed Message Delivery
Manager of Managers
MCP Server
Security Onion App for Splunk
Hypervisor
Reports
Onion AI Assistant

You can read more about these enterprise features at:

https://securityonion.com/pro

Training

Need training? Start with our free Security Onion Essentials training and then take a look at some of our other official Security Onion training!

https://securityonion.net/training

Security Onion Solutions Hardware Appliances

We know Security Onion's hardware needs, and our appliances are the perfect match for the platform. Leave the hardware research, testing, and support to us, so you can focus on what's important for your organization. Not only will you have confidence that your Security Onion deployment is running on the best-suited hardware, you will also be supporting future development and maintenance of the Security Onion project!

https://securityonionsolutions.com/hardware

Monday, March 9, 2026

Security Onion 3.0 Coming Soon!

Last week, we released Security Onion 2.4.210:

https://blog.securityonion.net/2026/03/security-onion-24210-now-available-with.html

This is our last major release in the 2.4 series! Our next major release will be Security Onion 3.0!

Security Onion 2.4

Security Onion 2.4 reached General Availability on August 15, 2023:

https://blog.securityonion.net/2023/08/security-onion-24-has-reached-general.html

Over the last 2.5 years, we've made lots of innovative changes to the platform but we kept the version number at 2.4. The time has come to move to Security Onion 3 to represent the innovation that we've already done and the innovation that we're planning to do!

Security Onion 3.0

Security Onion 3.0 is very similar to 2.4.210 and uses the exact same underlying operating system (Oracle Linux 9) and all of the same components with one exception: 3.0 no longer includes Stenographer and so full packet capture is handled by Suricata.

Also note that 3.0 will not work with anything but Oracle Linux 9. We will not test or support Ubuntu, Debian or any other distro. These other distros were not officially supported in 2.4 but we're officially removing them altogether in 3.0.

Upgrading from 2.4 to 3.0

Once Security Onion 3.0 is released, there will be a simple command to update from 2.4.210 to 3.0. If you are on an older version of 2.4.x, you will have to update to 2.4.210 first.

If you are still using Stenographer for your full packet capture, go ahead and change pcap mode to TRANSITION now so that Suricata can start doing pcap and old Stenographer data can roll off:

https://docs.securityonion.net/en/2.4/suricata.html#switching-pcap-from-stenographer-to-suricata

Security Onion Documentation printed book now updated for Security Onion 2.4.210!

We've been offering our Security Onion documentation in book form on Amazon for a few years and it's now been updated for the recently released Security Onion 2.4.210!

Thanks to Richard Bejtlich for writing the inspiring foreword!

Proceeds go to the Rural Technology Fund!

This edition has been updated for Security Onion 2.4.210 and includes a 20% discount code for our on-demand training and certification!

This book covers the following Security Onion topics:

First Time Users
Getting Started
Security Onion Console (SOC)
Security Onion Desktop
Network Visibility
Additional Network Visibility
Host Visibility
Third Party Integrations
Rules
Logs
Updating
Accounts
Services
Customizing for Your Environment
Tricks and Tips
Utilities
Help

Q&A

What is the difference between this book and the online documentation?

This book is the online documentation formatted specifically for print. It also includes an inspiring foreword by Richard Bejtlich that is not available anywhere else! Proceeds go to the Rural Technology Fund! Finally, the printed book includes a 20% discount code for our on-demand training and certification.

Who should get this book?

You should get this book if you work on airgap networks or simply want a portable reference that doesn't require an Internet connection or batteries! Also anyone who wants to donate to a worthy cause like Rural Technology Fund!

What is the difference between this edition and the previous edition?

This edition has been updated for Security Onion 2.4.210!

Where do we get it?

https://securityonion.com/book

Monday, March 2, 2026

Security Onion 2.4.210 Now Available with Updated Components and New Features including Local Model Support for Onion AI!

For Security Onion Pro customers, we've made major improvements for our popular new Onion AI Assistant. Many folks have been asking for local model support. If your local model has an OpenAI compatible endpoint, then this release can connect to it!

Onion AI is a huge leap forward in leveraging AI to assist you in triaging alerts, working incidents, and tuning your deployment! For more information, please see:

https://securityonion.net/docs/assistant

Updated Components

This release updates several components including:

Zeek to 8.0.6
Elasticsearch to 9.0.8
Docker to 29.2.1
Saltstack to 3006.19

Release Notes

Security Onion 2.4.210 upgrades Salt to version 3006.19. This version of Salt has a configuration option minimum_auth_version for the Salt master. By default, this value is set to 3 and only minions on version 3006.12 or later support that version and are able to authenticate with the salt-master service. For this reason, during the soup to 2.4.210, we set the minimum_auth_version to 0. Since minions automatically update every 15 minutes, this allows older minion versions to authenticate, run a highstate, and upgrade to 3006.19.

After seven days, a background process will change the minimum_auth_version from 0 to 3 and restart the salt-master service. Once this is done, any minions in the environment that have not upgraded to a version greater than 3006.12 will be unable to authenticate with the salt-master. The likely cause of this would be a minion that is offline. Additionally, if a user attempts to install a new node, using a version less than 2.4.200 (salt-minion 3006.16), the install will fail since the salt-minion will not be able to authenticate with the salt-master.

For more information, please see the full Release Notes:

https://securityonion.net/docs/release-notes

Known Issues

For a list of known issues, please see:

https://securityonion.net/docs/release-notes#known-issues

About Security Onion

Security Onion is a free and open platform built by defenders for defenders. It includes network visibility, host visibility, intrusion detection honeypots, log management, and case management.

For network visibility, we offer signature based detection via Suricata, rich protocol metadata and file extraction using your choice of either Zeek or Suricata, full packet capture, and file analysis. For host visibility, we offer the Elastic Agent which provides data collection, live queries via osquery, and centralized management using Elastic Fleet. Intrusion detection honeypots based on OpenCanary can be added to your deployment for even more enterprise visibility. All of these logs flow into Elasticsearch and we’ve built our own user interfaces for alerts, dashboards, threat hunting, case management, and grid management.

Security Onion has been downloaded over 2 million times and is being used by security teams around the world to monitor and defend their enterprises. Our easy-to-use Setup wizard allows you to build a distributed grid for your enterprise in minutes!

Documentation

You can find our online documentation here:

https://securityonion.net/docs

Documentation is always a work in progress. If you find documentation that needs to be updated, please let us know as described in the Feedback section below.

New Installations

If this is your first time installing Security Onion 2.4, then we highly recommend starting with an IMPORT installation as shown at:

https://securityonion.net/docs/first-time-users

Once you’re comfortable with your IMPORT installation, then you can move on to more advanced installations as shown at:

https://securityonion.net/docs/architecture

Existing 2.4 Installations

If you have an existing Security Onion 2.4 installation, you can update to the latest version using soup:

https://securityonion.net/docs/soup

2.3 EOL

As a reminder, Security Onion 2.3 reached End Of Life (EOL) on April 6, 2024:

https://blog.securityonion.net/2023/10/6-month-eol-notice-for-security-onion-23.html

Thanks