alert tcp $EXTERNAL_NET 443 -> $HOME_NET any (msg:"ET MALWARE Possible Updatre SSL Certificate cardiffpower"; flow:established,from_server; content:"|55 04 03|"; content:"|10|cardiffpower.com"; distance:1; within:17; content:"|55 04 03|"; distance:0; content:"|10|cardiffpower.com"; distance:1; within:17; classtype:domain-c2; sid:2017977; rev:3; metadata:attack_target Client_Endpoint, created_at 2014_01_17, deployment Perimeter, confidence Medium, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2019_10_25;)