alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/CopperStealer CnC Activity M3"; flow:established,to_server; http.request_line; content:"POST /info/"; startswith; fast_pattern; pcre:"/(?:retdl|fb|step) HTTP\/1\.1$/R"; http.content_type; content:"application/x-www-form-urlencoded"; bsize:33; http.request_body; content:"info="; startswith; content:!"&"; reference:md5,acd347a1839ee422d9393a09b5302ea2; classtype:command-and-control; sid:2031927; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_01_21, deployment Perimeter, malware_family Win32_CopperStealer, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_01_21;)