alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Malicious SSL certificate detected (FindPOS)"; flow:established,to_client; tls.cert_serial; content:"00:CD:2D:4A:53:08:27:AA:B4"; fast_pattern; tls.cert_subject; content:"O=Default Company Ltd"; reference:md5,a586db30ab21a02eee9e8ab2ebe8a2b5; reference:url,blog.team-cymru.org/2015/06/poseidon-and-the-backoff-pos-link/; classtype:domain-c2; sid:2021289; rev:4; metadata:attack_target Client_and_Server, created_at 2015_06_17, deployment Perimeter, deprecation_reason Age, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2024_04_02, reviewed_at 2024_04_02, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)