alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (msg:"ET SCAN Skipfish Web Application Scan Detected"; flow:established,to_server; threshold:type limit, count 10, seconds 60, track by_src; http.user_agent; content:"Mozilla/5.0 SF"; reference:url,isc.sans.org/diary.html?storyid=8467; reference:url,code.google.com/p/skipfish/; classtype:attempted-recon; sid:2010953; rev:6; metadata:created_at 2010_07_30, confidence Medium, signature_severity Informational, updated_at 2020_09_14;)