security onion local rules

https://docs.securityonion.net/en/2.3/local-rules.html?#id1. To unsubscribe from this group and stop receiving emails from it, send an email to. /opt/so/saltstack/local/pillar/minions/, https://www.proofpoint.com/us/threat-insight/et-pro-ruleset, https://www.snort.org/downloads/#rule-downloads, https://www.snort.org/faq/what-are-community-rules, https://snort.org/documents/registered-vs-subscriber, license fee per sensor (users are responsible for purchasing enough licenses for their entire deployment), Snort SO (Shared Object) rules only work with Snort not, same rules as Snort Subscriber ruleset, except rules only retrievable after 30 days past release, not officially managed/supported by Security Onion. Security Onion Peel Back the Layers of Your Enterprise Monday, January 26, 2009 Integrating Snort 3.0 (SnortSP) and Sguil in 3 Steps So once you have Snort 3.0 installed, what can you do with it? Backing up current local_rules.xml file. Security Onion offers the following choices for rulesets to be used by Snort/Suricata: ET Open optimized for Suricata, but available for Snort as well free For more information, see: https://rules.emergingthreats.net/open/ ET Pro (Proofpoint) optimized for Suricata, but available for Snort as well rules retrievable as released All alerts are viewable in Alerts, Dashboards, Hunt, and Kibana. Within 15 minutes, Salt should then copy those rules into /opt/so/rules/nids/local.rules. To get the best performance out of Security Onion, youll want to tune it for your environment. Integrated into the Security Onion, OSSEC is a host-based intrusion detection system (HIDS) that can conduct file integrity monitoring, local log monitoring, system process monitoring, and rootkit detection. Run so-rule without any options to see the help output: We can use so-rule to modify an existing NIDS rule. Copyright 2023 When setup is run on a new node, it will SSH to the manager using the soremote account and add itself to the appropriate host groups. Nodes will be configured to pull from repocache.securityonion.net but this URL does not actually exist on the Internet, it is just a special address for the manager proxy. Now we have to build the association between the host group and the syslog port group and assign that to our sensor node. Security Onion Layers Ubuntu based OS Snort, Suricata Snorby Bro Sguil Squert If you would like to pull in NIDS rules from a MISP instance, please see the MISP Rules section. If you would like to create a rule yourself and use it with Suricata, this guide might be helpful. Security Onion has Snort built in and therefore runs in the same instance. This can be done in the minion pillar file if you want the delay for just that minion, or it can be done in the global.sls file if it should be applied to all minions. Managing Rules; Adding Local Rules; Managing Alerts; High Performance Tuning; Tricks and Tips. One of those regular interventions is to ensure that you are tuning properly and proactively attempting to reach an acceptable level of signal to noise. The remainder of this section will cover the host firewall built into Security Onion. Start by creating Berkeley Packet Filters (BPFs) to ignore any traffic that you dont want your network sensors to process. . sigs.securityonion.net (Signature files for Security Onion containers) ghcr.io (Container downloads) rules.emergingthreatspro.com (Emerging Threats IDS rules) rules.emergingthreats.net (Emerging Threats IDS open rules) www.snort.org (Paid Snort Talos ruleset) github.com (Strelka and Sigma rules updates) See above for suppress examples. You can do the reverse unit conversion from MPa to psi, or enter any two units below:LED MSI Optix G242 24 inch IPS Gaming Monitor - Full HD - 144Hz Refresh Rate - 1ms Response time - Adaptive Sync for Esports (9S6-3BA41T-039) LED MSI OPTIX G272 Gaming Monitor 27" FHD IPS 144HZ 1MS Adaptive Sync (9S6-3CB51T-036) LG 27 FHD IPS 1ms 240Hz G . Security Onion is a free and open platform for threat hunting, enterprise security monitoring, and log management. Salt is a new approach to infrastructure management built on a dynamic communication bus. . If you need to manually update your rules, you can run the following on your manager node: If you have a distributed deployment and you update the rules on your manager node, then those rules will automatically replicate from the manager node to your sensors within 15 minutes. To enabled them, either revert the policy by remarking the ips_policy line (and run rule-update), or add the policy type to the rules in local.rules. 2GB RAM will provide decent performance for the Sguil client and retrieving packet captures from the server but also enough to run Security Onion in standalone mode for monitoring the local client and testing packet captures with tools like tcpreplay, In 2008, Doug Burks started working on Security Onion, a Linux distribution for intrusion detection, network security monitoring, and log management. In Security Onion, locally created rules are stored in /opt/so/rules/nids/local.rules. 3. epic charting system training Logs . The set of processes includes sguild, mysql, and optionally the Elastic stack (Elasticsearch, Logstash, Kibana) and Curator. It's simple enough to run in small environments without many issues and allows advanced users to deploy distributed systems that can be used in network enterprise type environments. For example, if you include a bad custom snort rule with incorrect syntax, the snort engine will fail . When you purchase products and services from us, you're helping to fund development of Security Onion! This directory stores the firewall rules specific to your grid. Write your rule, see Rules Format and save it. When I run sostat. The signature id (SID) must be unique. Saltstack states are used to ensure the state of objects on a minion. /opt/so/saltstack/local/salt/idstools/local.rules, "GPL ATTACK_RESPONSE id check returned root 2", /opt/so/saltstack/local/salt/strelka/rules, /opt/so/saltstack/local/salt/strelka/rules/localrules, /opt/so/saltstack/local/salt/strelka/rules/, https://github.com/Neo23x0/signature-base. In a distributed Security Onion environment, you only need to change the configuration in the manager pillar and then all other nodes will get the updated rules automatically. Data collection Examination Revision 39f7be52. I've just updated the documentation to be clearer. This will add the host group to, Add the desired IPs to the host group. 137 vi local.rules 138 sudo vi local.rules 139 vi cd .. 140 cd .. 141 vi securityonion.conf 142 sudo vi pulledpork/pulledpork.conf 143 sudo rule-update 144 history 145 vi rules/downloaded.rules 146 sudo vi local.rules 147 sudo vi rules/local.rules 160 sudo passwd david 161 sudo visudo 162 sudo vi rules/local.rules You can learn more about scapy at secdev.org and itgeekchronicles.co.uk. Salt sls files are in YAML format. For some alerts, your understanding of your own network and the business being transacted across it will be the deciding factor. However, generating custom traffic to test the alert can sometimes be a challenge. Security Onion. This error now occurs in the log due to a change in the exception handling within Salts event module. If so, then tune the number of AF-PACKET workers for sniffing processes. When editing these files, please be very careful to respect YAML syntax, especially whitespace. 5. Our instructors are the only Security Onion Certified Instructors in the world and our course material is the only authorized training material for Security Onion. From https://docs.saltstack.com/en/latest/: Salt is a core component of Security Onion 2 as it manages all processes on all nodes. In a distributed deployment, the manager node controls all other nodes via salt. Edit the /opt/so/rules/nids/local.rules file using vi or your favorite text editor: Paste the rule. Finally, from the manager, update the config on the remote node: You can manage threshold entries for Suricata using Salt pillars. Logs. Another consideration is whether or not the traffic is being generated by a misconfigured piece of equipment. While Vanderburgh County was the seventh-largest county in 2010 population with 179,703 people, it is also the eighth-smallest county in area in Indiana and the smallest in southwestern Indiana, covering only 236 square miles (610 km2). For example, if you dont care that users are accessing Facebook, then you can silence the policy-based signatures for Facebook access. If it is, then the most expedient measure may be to resolve the misconfiguration and then reinvestigate tuning. Inside of /opt/so/saltstack/local/salt/strelka/rules/localrules, add your YARA rules. In order to apply the threshold to all nodes, place the pillar in /opt/so/saltstack/local/pillar/global.sls. Was this translation helpful? If there are a large number of uncategorized events in the securityonion_db database, sguil can have a hard time of managing the vast amount of data it needs to process to present a comprehensive overview of the alerts. Adding local rules in Security Onion is a rather straightforward process. These are the files that will need to be changed in order to customize nodes. When configuring network firewalls for distributed deployments, youll want to ensure that nodes can connect as shown below. Finally, run so-strelka-restart to allow Strelka to pull in the new rules. Our products include both the Security Onion software and specialized hardware appliances that are built and tested to run Security Onion. The server is also responsible for ruleset management. There are three alerting engines within Security Onion: Suricata, Wazuh and Playbook (Sigma). Default pillar file: This is the pillar file located under /opt/so/saltstack/default/pillar/. Naming convention: The collection of server processes has a server name separate from the hostname of the box. Tracking. If this is a distributed deployment, edit local.rules on your master server and it will replicate to your sensors. Taiwan, officially the Republic of China (ROC), is a country in East Asia.It is located at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south. Started by Doug Burks, and first released in 2009, Security Onion has. It is now read-only. Security. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Please note that Suricata 6 has a 64-character limitation on the IP field in a threshold. Find Age Regression Discord servers and make new friends! Escalate local privileges to root level. We offer both training and support for Security Onion. Home About Us Bill Pay 877-213-8180 Product Library My accountItems of interest (0) Get your campus card Your campus card allows you to borrow books from the Library, use services at the student centre, make payments at Macquarie University retail outlets, and identify yourself during class tests and . "; reference: url,http://holisticinfosec.blogspot.com/2011/12/choose-2011-toolsmith-tool-of-year.html; content: "toolsmith"; flow:to_server; nocase; sid:9000547; metadata:policy security-ips; rev:1). If you have Internet access and want to have so-yara-update pull YARA rules from a remote Github repo, copy /opt/so/saltstack/local/salt/strelka/rules/, and modify repos.txt to include the repo URL (one per line). You can add NIDS rules in /opt/so/saltstack/local/salt/idstools/local.rules on your manager. If . You may want to bump the SID into the 90,000,000 range and set the revision to 1. After adding your rules, update the configuration by running so-strelka-restart on all nodes running Strelka. All the following will need to be run from the manager. If you built the rule correctly, then snort should be back up and running. With this functionality we can suppress rules based on their signature, the source or destination address and even the IP or full CIDR network block. Any pointers would be appreciated. We've been teaching Security Onion classes and providing Professional Services since 2014. The files in this directory should not be modified as they could possibly be overwritten during a soup update in the event we update those files. After viewing your redacted sostat it seems that the ICMP and UDP rules are triggering: Are you using SO with in a VM? Files here should not be modified as changes would be lost during a code update. To generate traffic we are going to use the python library scapy to craft packets with specific information to ensure we trigger the alert with the information we want: Craft the layer 2 information. . Ingest. Double-click the Setup script on the Desktop and follow the prompts to configure and start the Sguil processes. If you want to tune Wazuh HIDS alerts, please see the Wazuh section. Copyright 2023 According to NIST, which step in the digital forensics process involves drawing conclusions from data? At those times, it can be useful to query the database from the commandline. In a distributed deployment, the manager node controls all other nodes via salt. Once your rules and alerts are under control, then check to see if you have packet loss. The second only needs the $ character escaped to prevent bash from treating that as a variable. As you can see I have the Security Onion machine connected within the internal network to a hub. You can learn more about snort and writing snort signatures from the Snort Manual. These non-manager nodes are referred to as salt minions. You can then run curl http://testmynids.org/uid/index.html on the node to generate traffic which should cause this rule to alert (and the original rule that it was copied from, if it is enabled). If you are on a large network, you may need to do additional tuning like pinning processes to CPU cores. Security Onion includes best-of-breed free and open tools including Suricata, Zeek, Wazuh, the Elastic Stack and many others. In many of the use cases below, we are providing the ability to modify a configuration file by editing either the global or minion pillar file. Please note if you are using a ruleset that enables an IPS policy in /etc/nsm/pulledpork/pulledpork.conf, your local rules will be disabled. Fresh install of Security Onion 16.04.6.3 ISO to hardware: Two NICs, one facing management network, one monitoring mirrored port for test network Setup for Production Mode, pretty much all defaults, suricata create alert rules for /etc/nsm/local.rules and run rule-update Log into scapy/msf on kalibox, send a few suspicious packets To enable the Talos Subscriber ruleset in an already installed grid, modify the /opt/so/saltstack/local/pillar/minions/ file as follows: To add other remotely-accessible rulesets, add an entry under urls for the ruleset URL in /opt/so/saltstack/local/pillar/minions/: Copyright 2023 Cleaning up local_rules.xml backup files older than 30 days. Hi @Trash-P4nda , I've just updated the documentation to be clearer. In syslog-ng, the following configuration forwards all local logs to Security Onion. If you right click on the, You can learn more about snort and writing snort signatures from the. To verify the Snort version, type in snort -Vand hit Enter. to security-onion When I run 'rule-update' it give an error that there are no rules in /usr/local/lib/snort_dynamicrules. 1. 4. A node that has a port group and host group association assigned to it will allow those hosts to connect to those ports on that node. If SID 4321 is noisy, you can disable it as follows: From the manager, run the following to update the config: If you want to disable multiple rules at one time, you can use a regular expression, but make sure you enclose the full entry in single quotes like this: We can use so-rule to modify an existing NIDS rule. Apply the firewall state to the node, or wait for the highstate to run for the changes to happen automatically. Minion pillar file: This is the minion specific pillar file that contains pillar definitions for that node. These non-manager nodes are referred to as salt minions. Pillars are a Saltstack concept, formatted typically in YAML, that can be used to parameterize states via templating. to security-onion > > My rules is as follows: > > alert icmp any any -> (msg:"ICMP Testing"; sid:1000001; rev:1:) the rule is missing a little syntax, maybe try: alert icmp any any ->. Previously, in the case of an exception, the code would just pass. You do not have permission to delete messages in this group, Either email addresses are anonymous for this group or you need the view member email addresses permission to view the original message. alert icmp any any -> any any (msg: "ICMP Testing"; sid:1000001; rev:1;). . One thing you can do with it (and the one that most people are interested in) is to configure it for IDS mode. Within 15 minutes, Salt should then copy those rules into /opt/so/rules/nids/local.rules. Global pillar file: This is the pillar file that can be used to make global pillar assignments to the nodes. Try checking /var/log/nsm/hostname-interface/snortu-1.log for clues and please post the exact rule syntax you are attempting to use. Open /etc/nsm/rules/local.rules using your favorite text editor. 41 - Network Segmentation, VLANs, and Subnets. Identification. For more information about Salt, please see https://docs.saltstack.com/en/latest/. Long-term you should only run the rules necessary for > your environment. The reason I have a hub and not a switch is so that all traffic is forwarded to every device connected to it so security onion can see the traffic sent from the attacking kali linux machine, to the windows machines. The firewall state is designed with the idea of creating port groups and host groups, each with their own alias or name, and associating the two in order to create an allow rule. Here, we will show you how to add the local rule and then use the python library scapy to trigger the alert. To enable or disable SIDs for Suricata, the Salt idstools pillar can be used in the minion pillar file (/opt/so/saltstack/local/pillar/minions/_.sls). Adding local rules in Security Onion is a rather straightforward process. This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository. Some node types get their IP assigned to multiple host groups. If you pivot from that alert to the corresponding pcap you can verify the payload we sent. Here, we will show you how to add the local rule and then use the python library scapy to trigger the alert. However, generating custom traffic to test the alert can sometimes be a challenge. Our appliances will save you and your team time and resources, allowing you to focus on keeping your organization secure. In this file, the idstools section has a modify sub-section where you can add your modifications. Answered by weslambert on Dec 15, 2021. Security Onion is a free and open source platform for threat hunting, network security monitoring, and log management. The rule categories are Malware-Cnc, Blacklist, SQL injection, Exploit-kit, and rules from the connectivity ruleset Security: CVSS Score of 8 or higher Vulnerability age is four years old and newer The rule categories include Balanced and Connectivity with one additional category being App-detect When editing these files, please be very careful to respect YAML syntax, especially whitespace. Youll need to ensure the first of the two properly escapes any characters that would be interpreted by regex. /opt/so/saltstack/local/salt/firewall/hostgroups.local.yaml is where many default named hostgroups get populated with IPs that are specific to your environment. This first sub-section will discuss network firewalls outside of Security Onion. Alternatively, run salt -G 'role:so-sensor' cmd.run "so-strelka-restart" to restart Strelka on all sensors at once. Some of these refer to areas where data is stored, while others point to configuration files that can be modified to change how Security Onion interacts with various tools. But after I run the rule-update command, no alert is generated in Sguil based on that rule.It was working when I first installed Security Onion. Also ensure you run rule-update on the machine. Alternatively, run salt -G 'role:so-sensor' cmd.run "so-strelka-restart" to restart Strelka on all sensors at once. Add the following to the sensor minion pillar file located at. Though each engine uses its own severity level system, Security Onion converts that to a standardized alert severity: event.severity: 4 ==> event.severity_label: critical, event.severity: 3 ==> event.severity_label: high, event.severity: 2 ==> event.severity_label: medium, event.severity: 1 ==> event.severity_label: low. If you have multiple entries for the same SID, it will cause an error in salt resulting in all of the nodes in your grid to error out when checking in. Copyright 2023 Run the following command to get a listing of categories and the number of rules in each: In tuning your sensor, you must first understand whether or not taking corrective actions on this signature will lower your overall security stance. The easiest way to test that our NIDS is working as expected might be to simply access http://testmynids.org/uid/index.html from a machine that is being monitored by Security Onion. MISP Rules. Of course, the target IP address will most likely be different in your environment: destination d_tcp { tcp("192.168.3.136" port(514)); }; log { Edit the /opt/so/rules/nids/local.rules file using vi or your favorite text editor: sudo vi /opt/so/rules/nids/local.rules Paste the rule. Cannot retrieve contributors at this time. Backing up current downloaded.rules file before it gets overwritten. In the configuration window, select the relevant form of Syslog - here, it's Syslog JSON - and click. We can start by listing any rules that are currently modified: Lets first check the syntax for the add option: Now that we understand the syntax, lets add our modification: Once the command completes, we can verify that our modification has been added: Finally, we can check the modified rule in /opt/so/rules/nids/all.rules: To include an escaped $ character in the regex pattern youll need to make sure its properly escaped. https://securityonion.net/docs/AddingLocalRules. Diagnostic logs can be found in /opt/so/log/salt/. Assuming you have Internet access, Security Onion will automatically update your NIDS rules on a daily basis. /opt/so/saltstack/default/salt/firewall/portgroups.yaml, /opt/so/saltstack/default/salt/firewall/hostgroups.yaml, /opt/so/saltstack/default/salt/firewall/assigned_hostgroups.map.yaml, /opt/so/saltstack/local/salt/firewall/portgroups.local.yaml, /opt/so/saltstack/local/salt/firewall/hostgroups.local.yaml, /opt/so/saltstack/local/salt/firewall/assigned_hostgroups.local.map.yaml, /opt/so/saltstack/local/pillar/minions/_.sls, Allow hosts to send syslog to a sensor node, raw.githubusercontent.com (Security Onion public key), sigs.securityonion.net (Signature files for Security Onion containers), rules.emergingthreatspro.com (Emerging Threats IDS rules), rules.emergingthreats.net (Emerging Threats IDS open rules), github.com (Strelka and Sigma rules updates), geoip.elastic.co (GeoIP updates for Elasticsearch), storage.googleapis.com (GeoIP updates for Elasticsearch), download.docker.com (Docker packages - Ubuntu only), repo.saltstack.com (Salt packages - Ubuntu only), packages.wazuh.com (Wazuh packages - Ubuntu only), 3142 (Apt-cacher-ng) (if manager proxy enabled, this is repocache.securityonion.net as mentioned above), Create a new host group that will contain the IPs of the hosts that you want to allow to connect to the sensor. First off, I'll briefly explain security onion security Onion is the leading open source operating system for network security monitoring, intrusion detection, log management and threat hunting. This was implemented to avoid some issues that we have seen regarding Salt states that used the ip_interfaces grain to grab the management interface IP. How are they parsed? Local pillar file: This is the pillar file under /opt/so/saltstack/local/pillar/. You can find the latest version of this page at: https://securityonion.net/docs/AddingLocalRules. After adding your rules, update the configuration by running so-strelka-restart on all nodes running Strelka. This will execute salt-call state.highstate -l info which outputs to the terminal with the log level set to info so that you can see exactly whats happening: Many of the options that are configurable in Security Onion 2 are done via pillar assignments in either the global or minion pillar files. 3. Security Onion is a intrusion detection and network monitoring tool. For a quick primer on flowbits, see https://blog.snort.org/2011/05/resolving-flowbit-dependancies.html. The ip addresses can be random, but I would suggest sticking to RFC1918: Craft the layer 3 information Since we specified port 7789 in our snort rule: Use the / operator to compose our packet and transfer it with the send() method: Check Sguil/Squert/Kibana for the corresponding alert. The default allow rules for each node are defined by its role (manager, searchnode, sensor, heavynode, etc) in the grid. Alternatively, run salt -G 'role:so-sensor' cmd.run "so-strelka-restart" to restart Strelka on all sensors at once. I went ahead and put in the below rules under /etc/nsm/local.rules and ran the rule-update command. For more information, please see: # alert ip any any -> any any (msg:"GPL ATTACK_RESPONSE id check returned root"; content:"uid=0|28|root|29|"; classtype:bad-unknown; sid:2100498; rev:7; metadata:created_at 2010_09_23, updated_at 2010_09_23;), /opt/so/saltstack/local/pillar/minions/_.sls, "GPL ATTACK_RESPONSE id check returned root test", /opt/so/saltstack/default/pillar/thresholding/pillar.usage, /opt/so/saltstack/default/pillar/thresholding/pillar.example, /opt/so/saltstack/local/pillar/global.sls, /opt/so/saltstack/local/pillar/minions/.sls, https://docs.saltproject.io/en/latest/topics/troubleshooting/yaml_idiosyncrasies.html, https://redmine.openinfosecfoundation.org/issues/4377, https://blog.snort.org/2011/05/resolving-flowbit-dependancies.html. Launch your Ubuntu Server VM, log on with credentials provided at the beginning of this guide and open a terminal shell by double-clicking the Desktop shortcut. Its important to note that with this functionality, care should be given to the suppressions being written to make sure they do not suppress legitimate alerts. For example, if you had a web server you could include 80 and 443 tcp into an alias or in this case a port group. To enable the ET Pro ruleset in an already installed grid, modify the /opt/so/saltstack/local/pillar/minions/ file as follows: Since Shared Object rules wont work with Suricata, you may want to disable them using a regex like 're:soid [0-9]+' as described in the Managing Alerts section. This directory contains the default firewall rules. Please update your bookmarks. Adding local rules in Security Onion is a rather straightforward process. Revision 39f7be52. Security Onion Solutions, LLC is the creator and maintainer of Security Onion, a free and open platform for threat hunting, network security monitoring, and log management. Now that the configuration is in place, you can either wait for the sensor to sync with Salt running on the manager, or you can force it to update its firewall by running the following from the manager: Add the required ports to the port group. When configuring network firewalls for Internet-connected deployments (non-Airgap), youll want to ensure that the deployment can connect outbound to the following: In the case of a distributed deployment, you can configure your nodes to pull everything from the manager so that only the manager requires Internet access. Here are some of the items that can be customized with pillar settings: Currently, the salt-minion service startup is delayed by 30 seconds. 1. However, the exception is now logged. Host groups and port groups can be created or modified from the manager node using either so-allow, so-firewall or manually editing the yaml files. Revision 39f7be52. Have you tried something like this, in case you are not getting traffic to $HOME_NET? For example, suppose we want to disable SID 2100498. To enabled them, either revert the policy by remarking the ips_policy line (and run rule-update), or add the policy type to the rules in local.rules. Check out our NIDS tuning video at https://youtu.be/1jEkFIEUCuI! From the Command Line. Any line beginning with "#" can be ignored as it is a comment. /opt/so/saltstack/local/salt/firewall/assigned_hostgroups.local.map.yaml is where host group and port group associations would be made to create custom host group and port group assignements that would apply to all nodes of a certain role type in the grid. > To unsubscribe from this topic . To unsubscribe from this group and stop receiving emails from it, send an email to security-onio.@googlegroups.com. ELSA? You are an adult, at least 18 years of age, you are familiar with and understand the standards and laws of your local community regarding sexually-oriented media. If you cant run so-rule, you can modify the configuration manually in the manager pillar file at /opt/so/saltstack/local/pillar/minions/_.sls (where is manager, managersearch, standalone, or eval depending on the manager type that was chosen during install). For example, to check disk space on all nodes: If you want to force a node to do a full update of all salt states, you can run so-checkin. There may be entire categories of rules that you want to disable first and then look at the remaining enabled rules to see if there are individual rules that can be disabled.

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