alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO libwww-perl User-Agent"; flow:established,to_server; http.user_agent; content:"libwww-perl/"; startswith; nocase; reference:url,www.useragentstring.com/pages/useragentstring.php; classtype:attempted-recon; sid:2013030; rev:6; metadata:created_at 2011_06_14, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_12;)