ET MALWARE Trojan.Kwampirs Outbound GET request

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Trojan.Kwampirs Outbound GET request";
    flow:to_server,established;
    urilen:>21;
    http.method;
    content:"GET";
    http.uri;
    content:"?q=KT"; fast_pattern;
    pcre:"/\.(?:aspx?|php)\?q=(?=KT)(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/";
    http.user_agent;
    content:"Mozilla/"; depth:8;
    http.header_names;
    content:"|0d 0a|User-Agent|0d 0a|Host|0d 0a|"; depth:20;
    content:!"Referer|0d 0a|";
    content:!"Cookie|0d 0a|";
    content:!"Accept";
    reference:md5,1f1b5c16bbb62387fdf53e524a382006;
    reference:url,www.symantec.com/security_response/writeup.jsp?docid=2016-081923-2700-99&tabid=2;
    classtype:trojan-activity;
    sid:2023595; rev:6;
    metadata:attack_target Client_Endpoint, created_at 2016_12_09, deployment Perimeter, malware_family Trojan_Kwampirs, performance_impact Low, confidence High, signature_severity Major, updated_at 2020_11_04;
)