Security Onion 20111213 is now available! This resolves the following issues:
Issue 168: Suricata 1.1.1
As noted here, Suricata includes some anomaly detection in the form of decoder-events.rules and stream-events.rules. These two rulesets have been disabled in this update. You can manually re-enable them if desired.
New users can download and install the 20111103 ISO image using the instructions here. The step marked "Install Security Onion updates" will automatically install this update.
Existing Security Onion users can perform an in-place upgrade using the following command (if you're behind a proxy, remember to set your proxy variables as described in the FAQ):
sudo -i "curl -L http://sourceforge.net/projects/security-onion/files/security-onion-upgrade.sh > ~/security-onion-upgrade.sh && bash ~/security-onion-upgrade.sh"Note that the upgrade script is cumulative and will upgrade any older version of Security Onion to the most recent version (including any updates in between).
Switching to Suricata
If you're currently running Snort and would like to switch to Suricata, use the following commands to stop Snort, change the ENGINE variable in the config file, and then run PulledPork to download the Suricata-specific ruleset (if running Emerging Threats rules):
sudo nsm_sensor_ps-stop --only-snort-alert
sudo sed -i 's|ENGINE=snort|ENGINE=suricata|g' /etc/nsm/securityonion.conf