alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Prometei Botnet CnC Checkin"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/cgi-bin/prometei.cgi?r="; startswith; fast_pattern; content:"i="; distance:0; pcre:"/^[A-Z0-9]{16}/R"; reference:url,blog.talosintelligence.com/prometei-botnet-improves/; classtype:trojan-activity; sid:2044562; rev:1; metadata:attack_target Client_Endpoint, created_at 2023_03_10, deployment Perimeter, malware_family prometei, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_03_10;)