alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE ACR/Amatera Stealer CnC Exfil (POST) M1"; flow:established,to_server; urilen:5; http.method; content:"POST"; http.uri; content:"/Up/"; startswith; fast_pattern; pcre:"/^\x2fUp\x2f\w$/"; http.connection; content:"close"; http.content_type; content:"application/octet-stream"; http.header_names; content:!"|0d 0a|referer|0d 0a|"; nocase; http.request_body; content:"|50 4b 03 04|"; startswith; reference:md5,ed928383f02f205f92daf0b2d91c78de; classtype:command-and-control; sid:2062510; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_05_21, deployment Perimeter, malware_family Amatera, confidence High, signature_severity Critical, tag c2, updated_at 2025_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;)