alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE TonRAT CnC Activity (Powershell Payload)"; flow:established,to_client; flowbits:isset, ET.TonRAT; http.stat_code; content:"200"; http.content_len; byte_test:0,<=,680000,0,string,dec; http.response_body; content:"Add-Type -name win -member"; fast_pattern; content:"|22 2e|js|22|"; content:"return [Convert]::FromBase64String"; content:"|20|new|2d|object|20|ArgumentNullException|28 22|cipherText|22 29 3b 7d|"; content:"|20|new|2d|object|20|ArgumentNullException|28 22|key|22 29 3b 7d|"; content:"|20|new|2d|object|20|ArgumentNullException|28 22|iv|22 29 3b 7d|"; content:"new-Object System.Security.Cryptography.RijndaelManaged"; content:"New-Object System.Threading.Mutex"; content:"exit 1"; reference:url,blog.itochuci.co.jp/entry/2026/06/11/111500; classtype:command-and-control; sid:2071871; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, affected_product Windows_8, affected_product Windows_10, attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2026_08_31, deployment Perimeter, malware_family TonRAT, confidence High, signature_severity Major, tag c2, tag Blockchain, updated_at 2026_09_01, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol; target:dest_ip;)