alert http $HOME_NET any -> any any (msg:"ET SCAN Possible Nmap User-Agent Observed"; flow:to_server,established; http.user_agent; content:"|20|Nmap"; fast_pattern; classtype:web-application-attack; sid:2024364; rev:4; metadata:affected_product Any, attack_target Client_and_Server, created_at 2017_06_08, deployment Perimeter, performance_impact Low, confidence Medium, signature_severity Informational, updated_at 2020_08_06, reviewed_at 2024_05_06;)