ET MALWARE Win32/Koi Stealer CnC Checkin (GET)

Query · suricata

flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"php|3f|id|3d 26|subid|3d|"; fast_pattern;
pcre:"/^[a-zA-Z0-9]{8}$/R";
target:src_ip;
Raw source ET MALWARE Win32/Koi Stealer CnC Checkin (GET) · Suricata
Esc
Published by Emerging Threats Open ↗, licensed under BSD 3-Clause ↗. Line breaks added for readability; the rule is otherwise unchanged. 
alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET MALWARE Win32/Koi Stealer CnC Checkin (GET)";
    flow:established,to_server;
    http.method;
    content:"GET";
    http.uri;
    content:"php|3f|id|3d 26|subid|3d|"; fast_pattern;
    pcre:"/^[a-zA-Z0-9]{8}$/R";
    reference:url,malware-traffic-analysis.net/2025/01/23/index.html;
    classtype:command-and-control;
    sid:2059750; rev:2;
    metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_01_29, deployment Perimeter, malware_family KoiStealer, confidence High, signature_severity Major, tag c2, updated_at 2025_07_11, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;
    target:src_ip;
)

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