alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE PE downloaded malicious SSL certificate (CZ Solutions)"; flow:established,to_client; flowbits:isset,ET.http.binary; file_data; content:"|43 5a 20 53 6f 6c 75 74 69 6f 6e 20 43 6f 2e 2c 20 4c 74 64 2e|"; reference:url,www.fireeye.com/blog/technical/2014/07/the-little-signature-that-could-the-curious-case-of-cz-solution.html; classtype:domain-c2; sid:2018748; rev:3; metadata:attack_target Client_and_Server, created_at 2014_07_22, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, updated_at 2019_07_26, mitre_tactic_id TA0042, mitre_tactic_name Resource_Development, mitre_technique_id T1587, mitre_technique_name Develop_Capabilities;)