alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE APT OSX.XSLCmd CnC Beacon";
flow:established,to_server;
http.method;
content:"POST";
http.uri;
content:"/compose.aspx?s="; fast_pattern;
http.accept_lang;
content:"zh-cn"; bsize:5;
http.user_agent;
content:"Mozilla/4.0 (compatible|3b| MSIE 6.0|3b| Windows NT 5.1)";
reference:url,fireeye.com/blog/technical/malware-research/2014/09/forced-to-adapt-xslcmd-backdoor-now-on-os-x.html;
classtype:targeted-activity;
sid:2019136; rev:6;
metadata:attack_target Client_Endpoint, created_at 2014_09_08, deployment Perimeter, signature_severity Major, tag c2, updated_at 2020_05_04, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)