Versions (3)
Version DetailsCurrent
Rev: 1 • Oct 1, 2024, 12:00 PMET MALWARE Observed Malicious SSL Cert (Issuer contains CN=c2server)
alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Observed Malicious SSL Cert (Issuer contains CN=c2server)"; flow:established,to_client; tls.cert_issuer; content:"c2server"; nocase; fast_pattern; pcre:"/CN=(?:[^\r\n]+?\.)?c2server(?!\.)/i"; reference:url,github.com/trickster0/NamelessC2/tree/d075534d4be70fed2e0d3f85c8e90ccc7ac5bc85/NamelessServer; classtype:domain-c2; sid:2056383; rev:1; metadata:attack_target Client_and_Server, created_at 2024_10_01, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_10_01, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)
Oct 1, 2024, 12:00 PM
Oct 1, 2024, 12:00 PM
Oct 1, 2024, 10:00 PM
Jul 21, 2025, 9:34 PM
rules/emerging-malware.rules