alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Interlock RAT CnC Checkin"; flow:established,to_server; content:"U|11|i|df 7b 22|iptarget|22 3a|"; startswith; fast_pattern; content:"|22|domain|22 3a 20|"; distance:0; content:"|22|pcname|22 3a 20|"; distance:0; content:"|22|runas|22 3a 20|"; distance:0; content:"|22|typef|22 3a 20|"; distance:0; content:"|22|veros|22 3a 20|"; distance:0; reference:md5,2366128c20f42ee819251747eb3199a4; reference:url,blog.sekoia.io/interlock-ransomware-evolving-under-the-radar/; reference:url,community.emergingthreats.net/t/sig-et-trojan-interlock-ransomgroup-rat-initial-callback/2652; classtype:command-and-control; sid:2061804; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_04_22, deployment Perimeter, confidence High, signature_severity Critical, tag c2, updated_at 2025_04_22, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:src_ip;)