alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed Head Mare Domain (flexish .shop in TLS SNI)"; flow:established,to_server; tls.sni; dotprefix; content:".flexish.shop"; endswith; fast_pattern; reference:url,securelist.com/tr/head-mare-targets-trueconf-server-with-phantomcore/120988/; classtype:domain-c2; sid:2071456; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_and_Server, created_at 2026_08_11, deployment Perimeter, malware_family Phantomcore, performance_impact Low, confidence High, signature_severity Major, tag Head_Mare, updated_at 2026_08_11, mitre_tactic_id TA0037, mitre_tactic_name Command_And_Control, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)