alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE Ursnif Variant CnC Beacon 3";
flow:established,to_server;
http.method;
content:"GET";
http.user_agent;
content:"Mozilla/"; startswith;
http.request_body;
content:"|20 7c 20 22|0x"; fast_pattern;
content:"_"; distance:0;
content:"|22 20 7c 20|"; distance:0;
http.header_names;
content:!"|0d 0a|Accept";
content:!"Referer|0d 0a|";
reference:md5,f48f626cf746a2c3c73182c752c481b6;
reference:md5,8ab21ac9199d3ced2230924b90f49f0d;
classtype:command-and-control;
sid:2021814; rev:4;
metadata:attack_target Client_Endpoint, created_at 2015_09_23, deployment Perimeter, signature_severity Major, tag c2, updated_at 2024_03_10, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)