alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Observed Donot Group APT Domain (winterhero .buzz in TLS SNI)"; flow:established,to_server; tls.sni; content:"winterhero.buzz"; bsize:15; fast_pattern; reference:md5,e9e90fbd0322659e4775213b2a2c42ac; reference:url,twitter.com/GGGGh0st/status/1628244510835904512; classtype:trojan-activity; sid:2044384; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_02_28, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_03_30, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)