alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE Zloader CnC Activity (POST)";
flow:established,to_server;
http.method;
content:"POST";
http.uri;
content:"/";
urilen:1;
http.header_names;
content:"|0d 0a|rand|0d 0a|"; fast_pattern;
http.header;
pcre:"/[\r\n]rand\x3a\x20[a-z]{32,255}[\r\n]/Hi";
reference:url,zscaler.com/blogs/security-research/inside-zloader-s-latest-trick-dns-tunneling;
reference:url,community.emergingthreats.net/t/sigs-zloader/2268;
classtype:command-and-control;
sid:2058300; rev:1;
metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2024_12_16, deployment Perimeter, deployment SSLDecrypt, malware_family Zloader, confidence High, signature_severity Critical, tag c2, updated_at 2024_12_16, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;
)