alert http $HOME_NET any -> $EXTERNAL_NET !80 (msg:"ET MALWARE PurpleFox Backdoor/Rootkit Download Request M2"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/"; startswith; content:".zip?="; within:7; fast_pattern; pcre:"/^(?:0|1[678]\d{8})$/R"; http.host; pcre:"/^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$/"; http.header_names; content:"|0d 0a|Accept|0d 0a|"; startswith; content:"Accept-Encoding|0d 0a|User-Agent|0d 0a|Host|0d 0a|Connection|0d 0a|"; reference:url,blog.minerva-labs.com/malicious-telegram-installer-drops-purple-fox-rootkit; reference:md5,465dae978a41d566c7fabc9f5808487c; classtype:command-and-control; sid:2034871; rev:1; metadata:attack_target Client_Endpoint, created_at 2022_01_07, deployment Perimeter, malware_family PurpleFox, performance_impact Moderate, confidence High, signature_severity Major, updated_at 2022_01_07;)