alert tcp $EXTERNAL_NET any -> $HOME_NET any (msg:"MALWARE [PTsecurity] AMMYY RAT pkt checker #1"; flow:established, to_client; content:"|2d00|"; depth:2; dsize:2; stream_size:server, <,5; stream_size:client, <,39; flowbits:isset, FB301822_0; flowbits:unset, FB301822_0; threshold:type limit, track by_src, count 1, seconds 30; classtype:misc-activity; metadata:created_at 2017_7_12; reference:url, github.com/ptresearch/AttackDetection; sid:11001525; rev:1;)