alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Storm-2603 AK47C2 HTTP Backdoor CnC Checkin"; flow:established,to_server; http.method; content:"POST"; http.uri; bsize:1; content:"/"; http.header_names; bsize:48; content:"|0d 0a|Host|0d 0a|Content-Length|0d 0a|Content-Type|0d 0a|Accept|0d 0a 0d 0a|"; http.request_body; content:"|2d 6a 21 29 24 6a 6c|"; fast_pattern; startswith; reference:url,research.checkpoint.com/2025/before-toolshell-exploring-storm-2603s-previous-ransomware-operations/; classtype:trojan-activity; sid:2063872; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_08_01, deployment Perimeter, malware_family AK47C2, performance_impact Low, confidence High, signature_severity Major, tag storm_2603, updated_at 2025_08_01, mitre_tactic_id TA0037, mitre_tactic_name Command_And_Control, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel; target:src_ip;)