alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"MALWARE [PTsecurity] Malicious SSL connection (Orcus RAT)"; flow:established, to_server; content:"|1703|"; depth:2; content:"|0020|"; distance:1; within:2; fast_pattern; stream_size:server, <,1200; stream_size:server, >,700; stream_size:client, >,200; stream_size:client, <,600; flowbits:isset, FB369639_0; flowbits:unset, FB369639_0; threshold:type limit, track by_src, count 1, seconds 30; classtype:trojan-activity; metadata:created_at 2017_10_23; reference:url, github.com/ptresearch/AttackDetection; sid:11002136; rev:2;)