ET MALWARE Stealbit Variant Data Exfil M2

alert http $HOME_NET any -> $EXTERNAL_NET $HTTP_PORTS (
    msg:"ET MALWARE Stealbit Variant Data Exfil M2";
    flow:to_server,established;
    http.method;
    content:"POST";
    http.uri;
    content:!".html";
    http.content_type;
    content:"application/x-www-form-urlencoded"; bsize:33;
    http.request_body;
    content:"key="; startswith; fast_pattern;
    content:"&data="; within:100;
    pcre:"/^key=\w+\&data=/";
    http.header_names;
    content:!"|0d 0a|Referer|0d 0a|";
    reference:url,twitter.com/James_inthe_box/status/1425921372987944961;
    reference:url,blog.reversinglabs.com/blog/data-exfiltrator;
    classtype:command-and-control;
    sid:2033728; rev:4;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2021_08_13, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_05_30;
)