alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ABUSE.CH SSL Blacklist Malicious SSL certificate detected (TrickBot CnC)"; flow:established,to_client; tls.cert_serial; content:"00:AC:80:A0:72:11:64:DF:3F"; tls.cert_subject; content:"CN=localhost.localdomain"; fast_pattern; reference:url,sslbl.abuse.ch; classtype:domain-c2; sid:2023727; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_and_Server, created_at 2017_01_11, deployment Perimeter, deprecation_reason Age, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2024_04_03, reviewed_at 2024_04_03, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)