alert tcp $EXTERNAL_NET any -> $HOME_NET 445 (msg:"GPL NETBIOS SMB-DS ISystemActivator little endian bind attempt"; flow:established,to_server; content:"|00|"; depth:1; content:"|FF|SMB%"; within:5; distance:3; byte_test:1,!&,128,6,relative; content:"&|00|"; within:2; distance:56; content:"|5C|PIPE|5C 00|"; distance:4; nocase; byte_jump:2,-17,relative,from_beginning,little; isdataat:4,relative; content:"|05|"; byte_test:1,&,16,3,relative; content:"|0B|"; within:1; distance:1; content:"|A0 01 00 00 00 00 00 00 C0 00 00 00 00 00 00|F"; within:16; distance:29; flowbits:set,dce.isystemactivator.bind; flowbits:noalert; classtype:protocol-command-decode; sid:2103402; rev:4; metadata:created_at 2010_09_23, confidence Medium, signature_severity Informational, updated_at 2019_07_26;)