alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Amatera Stealer CnC Exfil (POST) M4"; flow:established,to_server; urilen:9; http.method; content:"POST"; http.uri; content:"/enc_up/"; startswith; fast_pattern; pcre:"/^\w$/R"; http.connection; content:"close"; http.content_type; content:"application/octet-stream"; http.header_names; content:!"|0d 0a|referer|0d 0a|"; nocase; reference:md5,d2ead81bf0cf01741abf09a49bc5e8a0; classtype:trojan-activity; sid:2063373; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, attack_target Client_and_Server, tls_state TLSDecrypt, created_at 2025_07_09, deployment Perimeter, malware_family Amatera, performance_impact Low, confidence High, signature_severity Major, updated_at 2025_07_09, mitre_tactic_id TA0037, mitre_tactic_name Command_And_Control, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel; target:src_ip;)