alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ABUSE.CH SSL Blacklist Malicious SSL certificate detected (Dridex)"; flow:established,to_client; tls.cert_serial; content:"00:"; startswith; tls.cert_subject; content:"O=Monsanto"; content:"OU=SmartPhones"; fast_pattern; reference:url,sslbl.abuse.ch; classtype:domain-c2; sid:2021596; rev:3; metadata:attack_target Client_and_Server, created_at 2015_08_05, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2024_04_09, mitre_tactic_id TA0042, mitre_tactic_name Resource_Development, mitre_technique_id T1587, mitre_technique_name Develop_Capabilities;)