alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/Milum CnC"; flow:established,to_server; content:"|0d 0a 0d 0a|md="; fast_pattern; http.method; content:"POST"; http.uri; content:".php"; endswith; http.content_type; content:"application/x-www-form-urlencoded"; bsize:33; http.request_body; content:"md="; startswith; content:"&nk="; distance:0; content:"&val="; distance:0; pcre:"/^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})$/R"; reference:md5,17b1a05fc367e52aada7bde07714666b; reference:url,securelist.com/wildpressure-targets-industrial-in-the-middle-east/96360/; classtype:command-and-control; sid:2029739; rev:2; metadata:attack_target Client_Endpoint, created_at 2020_03_24, deployment Perimeter, malware_family Win32_Milum, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_03_25;)