ET MALWARE Cobalt Strike Activity (GET)

Query · suricata

flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"/rpc"; bsize:4; fast_pattern;
http.header_names;
content:"|0d 0a|Host|0d 0a|Accept-Encoding|0d 0a|Accept-Language|0d 0a|User-Agent|0d 0a|";
content:!"Referer";
http.accept_lang;
content:"en-GB|3b|q=0.9,|20|*|3b|q=0.7"; bsize:20;
Raw source ET MALWARE Cobalt Strike Activity (GET) · Suricata
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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 Cobalt Strike Activity (GET)";
    flow:established,to_server;
    http.method;
    content:"GET";
    http.uri;
    content:"/rpc"; bsize:4; fast_pattern;
    http.header_names;
    content:"|0d 0a|Host|0d 0a|Accept-Encoding|0d 0a|Accept-Language|0d 0a|User-Agent|0d 0a|";
    content:!"Referer";
    http.accept_lang;
    content:"en-GB|3b|q=0.9,|20|*|3b|q=0.7"; bsize:20;
    reference:md5,f7810878118c08539c0cb0c60e4a23b7;
    reference:md5,8ccc051bbaf6dc9cb76bfea2bbd8f6d4;
    reference:url,www.cert.ssi.gouv.fr/uploads/CERTFR-2021-CTI-009.pdf;
    classtype:trojan-activity;
    sid:2034402; rev:2;
    metadata:attack_target Client_Endpoint, created_at 2021_11_10, deployment Perimeter, deployment SSLDecrypt, malware_family Cobalt_Strike, performance_impact Significant, confidence Medium, signature_severity Major, tag c2, updated_at 2024_04_04, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)

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