ET MALWARE CountLoader CnC Response

Query · suricata

flow:established,to_client;
flowbits:isset,ET.CountLoader;
http.response_body;
content:"eyJhbGciOiJ"; startswith;
content:"IsInR5cCI6IkpXVCJ9|2e|"; fast_pattern;
target:dest_ip;

Rule dependencies

⚠ Higher-order rule. It fires on other rules' alerts, not on raw events, so it cannot fire on its own. Deploy the rules it depends on too.

Depends on

Raw source ET MALWARE CountLoader CnC Response · Suricata
Esc
Published by Emerging Threats Open ↗, licensed under BSD 3-Clause ↗. Line breaks added for readability; the rule is otherwise unchanged. 
alert http $EXTERNAL_NET any -> $HOME_NET any (
    msg:"ET MALWARE CountLoader CnC Response";
    flow:established,to_client;
    flowbits:isset,ET.CountLoader;
    http.response_body;
    content:"eyJhbGciOiJ"; startswith;
    content:"IsInR5cCI6IkpXVCJ9|2e|"; fast_pattern;
    reference:url,silentpush.com/blog/countloader;
    reference:md5,8beece81a6dca4e5a8483f56917344ff;
    classtype:trojan-activity;
    sid:2072403; rev:1;
    metadata:affected_product Windows_Client, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2026_10_08, deployment Perimeter, deployment SSLDecrypt, malware_family CountLoader, confidence High, signature_severity Critical, updated_at 2026_10_08;
    target:dest_ip;
)

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