alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE DCRat CnC Activity"; flow:established,to_server; urilen:>100; http.method; content:"GET"; http.uri.raw; content:"=%3D"; fast_pattern; http.uri; content:".php?"; pcre:"/^\/[^\r\n]+\.php\?[a-f0-9]{32}(?:=(?:%3D|\x3d)*[A-Za-z0-9%\/]+&[a-f0-9]{32}){4,}=(?:%3D|\x3d)*[A-Za-z0-9%\/]+$/si"; http.header_names; content:"|0d 0a|Host|0d 0a 0d 0a|"; endswith; content:!"Referer"; content:!"Accept"; content:!"Cache"; threshold:type limit, track by_src, count 1, seconds 30; reference:md5,4467b54917f60b657e0c92df4296cbc1; classtype:command-and-control; sid:2029897; rev:3; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2020_04_13, deployment Perimeter, malware_family DCRat, confidence High, signature_severity Major, updated_at 2020_07_07;)