alert tcp $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE J-magic (nfsiod) Backdoor Magic Packet Inbound Request M3"; flow:not_established,to_server; flags:S; content:"Z4vE"; byte_test:4,>,16777216,0,big,relative; byte_test:2,>,0,0,big,relative; reference:url,blog.lumen.com/the-j-magic-show-magic-packets-and-where-to-find-them/; classtype:command-and-control; sid:2059805; rev:1; metadata:attack_target Client_Endpoint, tls_state plaintext, created_at 2025_01_31, deployment Perimeter, performance_impact Significant, confidence Medium, signature_severity Major, tag c2, updated_at 2025_01_31, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel; target:dest_ip;)