alert tcp $EXTERNAL_NET any -> $HOME_NET any (msg:"GPL RPC sadmind TCP PING"; flow:to_server,established; content:"|00 01 87 88|"; depth:4; offset:16; content:"|00 00 00 00|"; within:4; distance:4; content:"|00 00 00 00|"; depth:4; offset:8; reference:bugtraq,866; classtype:attempted-admin; sid:2101958; rev:6; metadata:created_at 2010_09_23, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)