alert tls $EXTERNAL_NET 443 -> $HOME_NET any (msg:"ET MALWARE CozyDuke APT Possible SSL Cert 3"; flow:established,to_client; tls.cert_subject; content:"C=--"; startswith; content:"ST=SomeState"; tls.cert_serial; content:"1b:3c"; fast_pattern; depth:5; reference:url,securelist.com/blog/69731/the-cozyduke-apt/; reference:md5,181a88c911b10d0fcb4682ae552c0de3; classtype:targeted-activity; sid:2020968; rev:4; metadata:attack_target Client_Endpoint, created_at 2015_04_22, deployment Perimeter, confidence Medium, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2024_04_01;)