alert icmp $EXTERNAL_NET any -> $HOME_NET any (msg:"GPL SCAN superscan echo"; dsize:8; itype:8; content:"|00 00 00 00 00 00 00 00|"; classtype:attempted-recon; sid:2100474; rev:5; metadata:created_at 2010_09_23, confidence Medium, signature_severity Informational, updated_at 2019_07_26;)