ET MALWARE Possible Dridex Download URI Struct with no referer

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Possible Dridex Download URI Struct with no referer";
    flow:established,to_server;
    http.method;
    content:"GET";
    http.uri;
    pcre:"/\/\d+\/\d+\.exe$/";
    http.user_agent;
    content:!"LogitechUpdate"; depth:14;
    http.request_line;
    content:".exe HTTP/1."; fast_pattern;
    http.header_names;
    content:!"Referer|0d 0a|";
    content:!"Accept-Language|0d 0a|";
    content:!"Cookie|0d 0a|";
    classtype:trojan-activity;
    sid:2021245; rev:10;
    metadata:created_at 2015_06_10, performance_impact Moderate, confidence Medium, signature_severity Major, updated_at 2024_04_08;
)