alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ABUSE.CH SSL Blacklist Malicious SSL certificate detected"; flow:established,to_client; tls.cert_subject; content:"C=US, ST=Denial, L=Springfield, O=Dis,"; fast_pattern; reference:url,sslbl.abuse.ch; classtype:domain-c2; sid:2021938; rev:5; metadata:attack_target Client_and_Server, created_at 2015_10_08, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2024_09_04, reviewed_at 2024_04_10, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)