ET MALWARE W32/Emotet CnC Checkin

alert http $HOME_NET any -> $EXTERNAL_NET [7080,8080,443,80,4143,995,21,50000,20,8090,8443,990,22] (
    msg:"ET MALWARE W32/Emotet CnC Checkin";
    flow:established,to_server;
    urilen:1;
    flowbits:set,ETPRO.Emotet;
    http.method;
    content:"GET";
    http.user_agent;
    content:"Mozilla/4.0 (compatible|3b 20|MSIE 7.0|3b 20|Windows NT 6.1|3b 20|"; depth:51;
    pcre:"/^(?:WOW64\x3b\s)?Trident\/[457]\.0\x3b\s*SLCC2\x3b\s\.NET\sCLR\s2\.0\.50727\x3b\s\.NET\sCLR\s3\.5\.30729\x3b\s(?:\x20\.NET\x20CLR\x203\.5\.30729\x3b\s)?\.NET\sCLR\s3\.0\.30729\x3b\sMedia\sCenter\sPC\s6\.0\x3b\s\.NET4\.0C\x3b\s\.NET4\.0E(?:\.NET4\.0E(?:\x3b\s)?)?(?:\x3b\sInfoPath\.3)?\)$/Rs";
    http.cookie;
    pcre:"/^[0-9]{3,5}\s*=(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})+$/i";
    http.start;
    content:"GET|20|/|20|HTTP/1.1|0d 0a|Cookie|3a 20|";
    http.header_names;
    content:"|0d 0a|Cookie|0d 0a|User-Agent|0d 0a|Host|0d 0a|Connection|0d 0a|"; depth:40; fast_pattern;
    content:!"Referer";
    content:!"Accept";
    reference:md5,d51ce75c66d1ac9f071b45b67fb8066c;
    classtype:command-and-control;
    sid:2035052; rev:9;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2018_05_04, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, updated_at 2020_08_27;
)