ET MALWARE Backdoor.Elise CnC Beacon 1 M1

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Backdoor.Elise CnC Beacon 1 M1";
    flow:to_server,established;
    http.method;
    content:"GET";
    http.uri;
    content:"/page_"; nocase; fast_pattern;
    content:".html"; nocase;
    pcre:"/\/[a-f0-9]{8}\/page_\d{8,10}\.html$/i";
    http.user_agent;
    content:"Mozilla/4.0 (compatible|3b 20|MSIE 8.0"; startswith;
    http.header_names;
    content:!"Accept-";
    content:!"Referer|0d 0a|";
    reference:md5,23ace716ec34bfd9c98efd79b23a01af;
    reference:url,github.com/pan-unit42/iocs/tree/master/lotusblossom;
    classtype:command-and-control;
    sid:2021274; rev:6;
    metadata:attack_target Client_Endpoint, created_at 2015_06_16, deployment Perimeter, signature_severity Major, tag c2, updated_at 2020_10_01, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)