ET MALWARE W32/Citadel.Arx Variant CnC Beacon 1

Query · suricata

flow:established,to_server;
http.uri;
content:"/rssfeed.php?a=";
pcre:"/^[^&]+?&\d+$/R";
http.header_names;
content:!"Referer|0d 0a|";
Raw source ET MALWARE W32/Citadel.Arx Variant CnC Beacon 1 · 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 -> $EXTERNAL_NET any (
    msg:"ET MALWARE W32/Citadel.Arx Variant CnC Beacon 1";
    flow:established,to_server;
    http.uri;
    content:"/rssfeed.php?a=";
    pcre:"/^[^&]+?&\d+$/R";
    http.header_names;
    content:!"Referer|0d 0a|";
    reference:url,botnetlegalnotice.com/citadel/files/Patel_Decl_Ex20.pdf;
    reference:url,www.fireeye.com/blog/technical/cyber-exploits/2013/11/the-dual-use-exploit-cve-2013-3906-used-in-both-targeted-attacks-and-crimeware-campaigns.html;
    classtype:command-and-control;
    sid:2017690; rev:3;
    metadata:attack_target Client_Endpoint, created_at 2013_11_07, deployment Perimeter, signature_severity Major, tag c2, updated_at 2020_04_27, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)

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