ET MALWARE Possible Emissary External IP Lookup

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Possible Emissary External IP Lookup";
    flow:established,to_server;
    urilen:12;
    http.method;
    content:"GET";
    http.uri;
    content:"/index.shtml";
    http.host;
    content:"b4secure.com"; endswith; fast_pattern;
    http.user_agent;
    content:"Mozilla/4.0 (compatible|3b 20|MSIE 6.0|3b 20|Win32)"; bsize:41;
    http.header_names;
    content:!"Accept";
    content:!"Referer|0d 0a|";
    reference:url,researchcenter.paloaltonetworks.com/2016/10/unit42-psa-conference-invite-used-lure-operation-lotus-blossom-actors/;
    classtype:external-ip-check;
    sid:2023470; rev:5;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2016_10_31, deployment Perimeter, malware_family Emissary, malware_family Lotus_Blossom, performance_impact Low, confidence High, signature_severity Informational, updated_at 2024_11_26, mitre_tactic_id TA0007, mitre_tactic_name Discovery, mitre_technique_id T1614, mitre_technique_name System_Location_Discovery;
)