alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"MALWARE [PTsecurity] TrickBot.Spy SSL connection cert"; flow:established, to_client; content:"|308203|"; depth:600; content:"|308202|"; distance:1; within:3; content:"|a003020102020900|"; distance:1; within:8; flowbits:noalert; flowbits:set, FB566923_; threshold:type limit, track by_src, count 1, seconds 30; classtype:trojan-activity; metadata:created_at 2018_5_11; reference:url, github.com/ptresearch/AttackDetection; sid:11002938; rev:1;)