ET MALWARE Cobalt Strike Activity (GET)

Query · suricata

flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"/api/2"; bsize:6; fast_pattern;
http.header_names;
content:"|0d 0a|Host|0d 0a|User-Agent|0d 0a|Connection|0d 0a|Cache-Control|0d 0a 0d 0a|"; bsize:49;
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:"/api/2"; bsize:6; fast_pattern;
    http.header_names;
    content:"|0d 0a|Host|0d 0a|User-Agent|0d 0a|Connection|0d 0a|Cache-Control|0d 0a 0d 0a|"; bsize:49;
    reference:md5,1cc3c8d9bdc43fd4f792b40fdf1333bc;
    reference:url,blog.talosintelligence.com/2021/11/attackers-use-domain-fronting-technique.html;
    classtype:trojan-activity;
    sid:2034529; rev:1;
    metadata:attack_target Client_Endpoint, created_at 2021_11_22, deployment Perimeter, malware_family Cobalt_Strike, confidence Medium, signature_severity Major, updated_at 2021_11_22, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1001, mitre_technique_name Data_Obfuscation;
)

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