alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE SUR SSL Cert APT1"; flow:established,to_client; tls.cert_serial; content:"20:82:92:3F:43:2C:8F:75:B7:EF:0F:6A:D9:3C:8E:5D"; fast_pattern; tls.cert_subject; content:"CN=SUR"; reference:url,www.mandiant.com/apt1; classtype:targeted-activity; sid:2016468; rev:5; 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_22;)