alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed TA444 Domain (datasend .fun in TLS SNI)"; flow:established,to_server; tls.sni; dotprefix; content:".datasend.fun"; endswith; fast_pattern; classtype:trojan-activity; sid:2047919; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_09_05, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_10_05, reviewed_at 2023_10_05, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)