alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ABUSE.CH SSL Blacklist Malicious SSL certificate detected (Shifu)"; flow:established,to_client; tls.cert_serial; content:"00:C1:FB:CD:CD:FF:15:B4:03"; fast_pattern; tls.cert_subject; content:"O=Internet|20|Widgits|20|Pty|20|Ltd"; reference:url,sslbl.abuse.ch; reference:md5,c493fbc74573c2c125ff57b1bf15e4be; classtype:domain-c2; sid:2022065; rev:4; metadata:attack_target Client_and_Server, created_at 2015_11_11, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_08, mitre_tactic_id TA0042, mitre_tactic_name Resource_Development, mitre_technique_id T1587, mitre_technique_name Develop_Capabilities;)