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README.md

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 - [3CORESec NIDS - Lateral Movement](https://dtection.io/ruleset/3cs_lateral) - Suricata ruleset focusing on lateral movement techniques (paid).
 - [3CORESec NIDS - Sinkholes](https://dtection.io/ruleset/3cs_sinkholes) - Suricata ruleset focused on a curated list of public malware sinkholes (free).
 - [PAW Patrules](https://pawpatrules.fr) - Another free (CC BY-NC-SA) collection of rules for the Suricata engine.
+- [opnsense-suricata-nmaps](https://github.com/aleksibovellan/opnsense-suricata-nmaps) - OPNSense's Suricata IDS/IPS Detection Rules Against NMAP Scans.
 
 
 ## Rule/Security Content Management and Handling