alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET SCAN Arachni Scanner Web Scan"; flow:established,to_server; threshold:type limit, track by_src, count 1, seconds 300; http.user_agent; content:"Arachni/"; pcre:"/Arachni\/v?\d\.\d\.\d$/i"; reference:url,arachni-scanner.com; reference:url,github.com/Zapotek/arachni; classtype:attempted-recon; sid:2014869; rev:6; metadata:created_at 2012_06_07, confidence Medium, signature_severity Informational, updated_at 2020_06_09;)