alert tcp-pkt $HOME_NET any -> $EXTERNAL_NET any (msg:"ET HUNTING implant.js CnC Handshake (HS_SYN)"; flow:established,to_server; flowbits:set,ET.implantjs.syn; dsize:2; content:"|13 37|"; reference:url,github.com/captainGeech42/implant.js; reference:url,districtcon.org/bios-and-talks-2025/implantjs-modular-malware; classtype:bad-unknown; sid:2060254; rev:2; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Mac_OSX, affected_product Linux, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_02_21, deployment Perimeter, malware_family implant_js, performance_impact Low, confidence High, signature_severity Major, tag c2, updated_at 2026_05_21, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:src_ip;)