ET MALWARE AutoIt3.exe Downloaded via Powershell

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE AutoIt3.exe Downloaded via Powershell";
    flow:established,to_server;
    flowbits:set,ET.AutoItDownload;
    flowbits:noalert;
    urilen:12;
    http.method;
    content:"GET";
    http.uri;
    content:"/AutoIt3.exe"; fast_pattern;
    http.user_agent;
    content:"WindowsPowerShell/";
    http.header_names;
    content:!"|0d 0a|Referer|0d 0a|"; nocase;
    threshold:type limit, count 1, seconds 300, track by_src;
    reference:md5,0286120018b92f5827ff9ad84696e7b3;
    classtype:misc-activity;
    sid:2052523; rev:1;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state plaintext, created_at 2024_05_09, deployment Perimeter, confidence High, signature_severity Major, tag c2, updated_at 2024_05_09, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;
)