ET MALWARE Qbot Payload Request (2023-03-21) M4

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Qbot Payload Request (2023-03-21) M4";
    flow:established,to_server;
    urilen:<21;
    http.method;
    content:"GET";
    http.uri;
    content:".php?4"; fast_pattern;
    isdataat:!5,relative;
    content:!"=";
    pcre:"/^\/(?P<base_dir>[a-z]{2,4})\/(?P=base_dir)\.php\?4[0-9]{4}$/";
    http.header_names;
    content:!"|0d 0a|Referer|0d 0a|";
    classtype:trojan-activity;
    sid:2044727; rev:2;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2023_03_22, deployment Perimeter, deployment SSLDecrypt, malware_family Qbot, performance_impact Moderate, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_03_24;
    target:src_ip;
)