alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE ABUSE.CH SSL Blacklist Malicious SSL certificate detected (Dridex CnC)"; flow:established,to_client; tls.cert_serial; content:"00:"; startswith; tls.cert_subject; content:"O=Microsoft"; fast_pattern; content:"OU=Widgits pty"; reference:md5,32230d747829dcf77841f594aa54915a; reference:url,sslbl.abuse.ch; classtype:domain-c2; sid:2021529; rev:4; metadata:attack_target Client_and_Server, created_at 2015_07_24, 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;)