alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE DarkHotel Downloader CnC Beacon 1";
flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"2.php?jpg="; fast_pattern;
content:!"&"; distance:0;
pcre:"/\/[a-z]+2\.php\?jpg=[^&]+$/";
http.header_names;
content:!"Accept";
content:!"Referer|0d 0a|";
reference:url,labs.bitdefender.com/2017/07/inexsmar-an-unusual-darkhotel-campaign/;
classtype:targeted-activity;
sid:2024482; rev:3;
metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2017_07_20, deployment Perimeter, malware_family DarkHotel, confidence High, signature_severity Major, tag Targeted, tag APT, tag DarkHotel, tag c2, updated_at 2020_08_10, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;
)