alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE MSIL/Agent.BIC Variant CnC Checkin";
flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"?response=";
content:"&cpu="; distance:0;
content:"&gpu="; distance:0;
content:"&ram="; distance:0;
content:"&name="; distance:0;
content:"&os="; distance:0;
http.header_names;
content:!"Referer";
content:!"User-Agent";
content:!"Accept";
content:!"Cache";
reference:md5,C6C781F0ED065476A4297C2AC96A6D83;
classtype:command-and-control;
sid:2025359; rev:2;
metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2018_02_15, deployment Perimeter, malware_family Agent_BIC, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_08_24;
)