alert tcp any any -> any any (msg:"ET MALWARE DPRK HIDDEN COBRA Botnet C2 Host Beacon"; flow:established,to_server; content:"|1b 17 e9 e9 e9 e9|"; depth:6; fast_pattern; reference:url,www.us-cert.gov/ncas/alerts/TA17-164A; classtype:command-and-control; sid:2024383; rev:3; metadata:attack_target Client_Endpoint, created_at 2017_06_14, deployment Perimeter, confidence Medium, signature_severity Major, tag c2, updated_at 2020_08_19, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)