alert tcp-pkt $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE MonsterV2 Stealer CnC Checkin"; flow:established,to_server; content:"d2ZXJzaW9u"; offset:2; fast_pattern; base64_decode:bytes 120, offset 0; base64_data; content:"version"; depth:9; content:"build_name"; within:12; reference:md5,73e43654e9f3df0d07d25051b2d3cfeb; classtype:trojan-activity; sid:2061200; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, attack_target Client_and_Server, tls_state plaintext, created_at 2025_03_31, deployment Perimeter, malware_family Aurotun, malware_family MonsterV2, performance_impact Low, confidence High, signature_severity Major, tag InfoStealer, updated_at 2025_03_31, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1001, mitre_technique_name Data_Obfuscation; target:src_ip;)