alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Interlock Ransomware Fake Updater CnC Command (Terminate)"; flow:established,to_client; flowbits:isset,ET.Interlock; http.stat_code; content:"200"; http.content_len; content:"4"; http.response_body; bsize:4; content:"ooff"; fast_pattern; reference:url,blog.sekoia.io/interlock-ransomware-evolving-under-the-radar/; classtype:trojan-activity; sid:2062407; rev:1; metadata:attack_target Client_Endpoint, created_at 2025_05_16, deployment Perimeter, malware_family Interlock, performance_impact Low, confidence High, signature_severity Critical, updated_at 2025_05_19, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)