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;)