ET MALWARE Suspected TA404 SIGNBT Backdoor Activity (POST)

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Suspected TA404 SIGNBT Backdoor Activity (POST)";
    flow:established,to_server;
    urilen:>20;
    http.method;
    content:"POST";
    http.uri;
    content:".php"; endswith;
    http.content_type;
    content:"application/x-www-form-urlencoded"; bsize:33;
    http.header_names;
    content:"|0d 0a|Connection|0d 0a|Content-Type|0d 0a|User-Agent|0d 0a|Content-Length|0d 0a|Host|0d 0a 0d 0a|"; fast_pattern; bsize:64;
    http.request_body;
    pcre:"/^(?:[a-zA-Z0-9]{3,7})\x3d(?:[A-Za-z0-9+/]{64})$/";
    reference:md5,9b62352851c9f82157d1d7fcafeb49d3;
    reference:url,securelist.com/unveiling-lazarus-new-campaign/110888/;
    classtype:trojan-activity;
    sid:2049001; rev:1;
    metadata:attack_target Client_Endpoint, created_at 2023_10_31, deployment Perimeter, performance_impact Moderate, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_10_31, reviewed_at 2023_10_31;
    target:src_ip;
)