ET MALWARE CloudAtlas APT Related Maldoc Activity M5 (GET)

Query · suricata

flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"/?"; startswith;
content:"_?"; within:12; fast_pattern;
content:"="; within:5;
content:!"|2e|";
http.user_agent;
content:"|3b 20|ms-office|3b 20|";
http.header_names;
content:!"Referer";
target:src_ip;
Raw source ET MALWARE CloudAtlas APT Related Maldoc Activity M5 (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 CloudAtlas APT Related Maldoc Activity M5 (GET)";
    flow:established,to_server;
    http.method;
    content:"GET";
    http.uri;
    content:"/?"; startswith;
    content:"_?"; within:12; fast_pattern;
    content:"="; within:5;
    content:!"|2e|";
    http.user_agent;
    content:"|3b 20|ms-office|3b 20|";
    http.header_names;
    content:!"Referer";
    reference:md5,b3de2f04ceb97f8e9164399649433e1e;
    reference:url,www.facct.ru/blog/cloud-atlas;
    classtype:trojan-activity;
    sid:2049735; rev:1;
    metadata:attack_target Client_Endpoint, created_at 2023_12_19, deployment Perimeter, deployment SSLDecrypt, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_12_19;
    target:src_ip;
)

Detection rules belong to the projects that publish them and remain under their own licenses. This site indexes and links to them; it claims no rights in them.