alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Sednit Connectivity Check 0 Byte POST"; flow:established,to_server; http.method; content:"POST"; http.uri; content:!"=http"; content:"/?"; pcre:"/\.[a-z]{3,4}\/\?[A-Za-z0-9]+=(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})$/"; http.header; header_lowercase; content:"content-length|3a 20|0|0d 0a|"; fast_pattern; http.host; content:"google."; within:10; pcre:"/^(?:www\.)?google(?:\.[a-z]{2,3})+$/"; http.header_names; to_lowercase; content:!"|0d 0a|referer|0d 0a|"; reference:url,blog.trendmicro.com/trendlabs-security-intelligence/an-in-depth-look-at-how-pawn-storms-java-zero-day-was-used; classtype:targeted-activity; sid:2021506; rev:8; metadata:created_at 2015_07_22, performance_impact Significant, signature_severity Major, updated_at 2024_04_28;)