alert tcp $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE SillyRAT CnC Command Inbound (Keylogger:On)"; flow:established,to_client; dsize:<32; content:"a2V5bG9nZ2VyOm9u|0a|"; startswith; threshold:type limit,count 1,seconds 300,track by_dst; reference:url,github.com/hash3liZer/SillyRAT; classtype:command-and-control; sid:2063513; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Linux, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_07_16, deployment Perimeter, malware_family SillyRat, confidence High, signature_severity Critical, updated_at 2025_07_16, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1095, mitre_technique_name Non_Application_Layer_Protocol; target:dest_ip;)