Rule History

alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Oyster Backdoor Domain in TLS SNI (postmastersoriginals .com)"; flow:established,to_server; tls.sni; bsize:24; content:"postmastersoriginals.com"; fast_pattern; reference:url,hunt.io/blog/a-simple-approach-to-discovering-oyster-backdoor-infrastructure; classtype:trojan-activity; sid:2055261; rev:1; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2024_08_13, deployment Perimeter, malware_family Oyster_Backdoor, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_08_13, reviewed_at 2024_12_17, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)