alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed TA409 Related Domain (navercorp .ru in TLS SNI)"; flow:established,to_server; tls.sni; bsize:12; content:"navercorp.ru"; fast_pattern; reference:md5,9e6a2914a35256dd450db549fb975f45; reference:url,twitter.com/suyog41/status/1697536913610314016; classtype:domain-c2; sid:2047882; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_09_01, deployment Perimeter, deprecation_reason Age, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_01, reviewed_at 2024_04_01, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)