alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Fake Virtually SSL Cert APT1"; flow:established,to_client; tls.cert_issuer; content:"O=www.virtuallythere.com"; content:"OU=new"; content:"CN=new"; tls.cert_subject; content:"O=www.virtuallythere.com"; fast_pattern; content:"OU=new"; content:"CN=new"; reference:url,www.mandiant.com/apt1; classtype:targeted-activity; sid:2016462; rev:4; metadata:attack_target Client_Endpoint, created_at 2013_02_22, deployment Perimeter, confidence High, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2022_03_21;)