alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Win32/CHAOS RAT/AlfaC2 Checkin"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/device"; bsize:7; http.request_body; content:"|7b 22|hostname|22 3a 22|"; startswith; fast_pattern; content:"|22 2c 22|username|22 3a 22|"; distance:0; content:"|22 2c 22|user|5f|id|22 3a 22|"; distance:0; content:"|22 2c 22|os|5f|name|22 3a 22|"; distance:0; content:"|22 2c 22|os|5f|arch|22 3a 22|"; distance:0; content:"|22 2c 22|mac|5f|address|22 3a 22|"; distance:0; content:"|22 2c 22|local|5f|ip|5f|address|22 3a 22|"; distance:0; content:"|22 2c 22|port|22 3a 22|"; distance:0; content:"|22 2c 22|fetched|5f|unix|22 3a|"; distance:0; http.header_names; content:!"|0d 0a|Referer|0d 0a|"; reference:md5,dbe9be7d2f99e434ce1504a8992b11a8; classtype:command-and-control; sid:2037145; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_06_28, deployment Perimeter, malware_family Win32_CHAOS, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_11_27, reviewed_at 2025_01_22;)