ET MALWARE Fileless infection dropped by EK CnC Beacon

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Fileless infection dropped by EK CnC Beacon";
    flow:established,to_server;
    http.uri;
    content:"hl=";
    content:"source=";
    content:"aq=";
    content:"aqi=";
    content:"aql="; fast_pattern;
    content:"oq=";
    http.header;
    content:!"google.";
    content:"Content-Type|3a 20|application/x-www-form-urlencoded|0d 0a|"; depth:49;
    http.header_names;
    content:!"User-Agent|0d 0a|";
    content:!"Accept";
    content:!"Referer|0d 0a|";
    classtype:command-and-control;
    sid:2020734; rev:5;
    metadata:attack_target Client_Endpoint, created_at 2015_03_24, deployment Perimeter, performance_impact Moderate, confidence High, signature_severity Major, tag c2, updated_at 2024_04_15, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)