alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE OSX/Proton.C/D Domain (handbrakestore .com in TLS SNI)"; flow:established,to_server; tls.sni; content:"handbrakestore.com"; bsize:18; fast_pattern; nocase; reference:url,www.welivesecurity.com/2017/10/20/osx-proton-supply-chain-attack-elmedia; classtype:trojan-activity; sid:2024891; rev:5; metadata:affected_product Mac_OSX, attack_target Client_Endpoint, created_at 2017_10_20, deployment Perimeter, malware_family Proton, performance_impact Moderate, confidence High, signature_severity Major, updated_at 2022_03_18, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)