[WEB-ATTACKS] Nessus User Agent

alert any $EXTERNAL_NET any -> $HOME_NET any (msg: "[WEB-ATTACKS] Nessus User Agent"; content: "User-Agent"; nocase; content: "Nessus"; nocase; content:!"inessus"; nocase; content: !"www.nessus.org"; nocase; parse_src_ip: 1; parse_dst_ip: 2; content:!"Rule"; nocase; content:!"drop"; content:!"tmm"; nocase; reference:url,www.nessus.org; reference:url,doc.emergingthreats.net/2002664; xbits: set,recon,track ip_src,expire 86400; default_proto:tcp; default_dst_port: $HTTP_PORT; classtype:attempted-recon; sid:5001865; rev:4;)