alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ABUSE.CH SSL Blacklist Malicious SSL certificate detected (Retefe CnC)"; flow:established,to_client; tls.certs; content:"|2a 86 48 86 f7 0d 01 09 01|"; tls.cert_subject; content:"ST=Zurich"; content:"L=Zurich"; content:"IT"; content:"CN=default"; content:"me@myhost.mydomain"; reference:url,sslbl.abuse.ch; classtype:domain-c2; sid:2022129; rev:4; metadata:attack_target Client_and_Server, created_at 2015_11_23, deployment Perimeter, malware_family Banking_Trojan, malware_family Retefe, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_18, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)