ET MALWARE Win32/Nivdort Posting Data 2

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Win32/Nivdort Posting Data 2";
    flow:established,to_server;
    content:"|0d 0a 0d 0a|env="; fast_pattern;
    http.method;
    content:"POST";
    http.uri;
    content:".php"; endswith;
    http.request_body;
    pcre:"/^env=(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=|[A-Za-z0-9+/]{4})/";
    http.content_type;
    content:"application/x-www-form-urlencoded"; depth:33; endswith;
    http.protocol;
    content:"HTTP/1.0";
    http.header_names;
    content:!"User-Agent|0d 0a|";
    content:!"Accept-";
    content:!"Referer|0d 0a|";
    reference:url,www.microsoft.com/security/portal/threat/encyclopedia/entry.aspx?Name=TrojanSpy%3AWin32/Nivdort;
    classtype:trojan-activity;
    sid:2022281; rev:4;
    metadata:created_at 2015_12_18, malware_family Win32_Nivdort, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_11_05;
)