alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Observed Malicious SSL Cert (MageCart)"; flow:established,from_server; tls.cert_serial; content:"00:B3:4B:42:19:50:7A:3B:55:78:3D:6D:FD:12:54:C8:88"; classtype:domain-c2; sid:2029102; rev:2; metadata:attack_target Client_and_Server, created_at 2019_12_09, deployment Perimeter, malware_family MageCart, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_10_24, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)