alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE PurpleFox Backdoor/Rootkit Checkin"; flow:established,to_server; stream_size:server,<,5; content:"|37 39 78|"; startswith; content:"|98 98 98|"; distance:1; within:3; content:"|98 98|"; distance:2; within:2; content:"|98 98 98 20 fc|"; distance:1; within:5; fast_pattern; reference:md5,465dae978a41d566c7fabc9f5808487c; reference:url,blog.minerva-labs.com/malicious-telegram-installer-drops-purple-fox-rootkit; classtype:command-and-control; sid:2034873; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2022_01_10, deployment Perimeter, malware_family PurpleFox, performance_impact Low, confidence High, signature_severity Major, updated_at 2022_01_10;)