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SID: 2039793 • Source: et/open

Versions (5)

Version DetailsCurrent

Rev: 1Nov 16, 2022, 12:00 PM

ET MALWARE Observed Malicious SSL/TLS Certificate (CobaltStrike C2)

alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Observed Malicious SSL/TLS Certificate (CobaltStrike C2)"; flow:from_server,established; tls.cert_subject; content:"CN=msisfx.com"; fast_pattern; classtype:domain-c2; sid:2039793; rev:1; metadata:attack_target Client_and_Server, created_at 2022_11_16, deployment Perimeter, performance_impact Low, confidence High, signature_severity Major, tag SSL_Malicious_Cert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_11_16, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1071, mitre_technique_name Application_Layer_Protocol;)

Nov 16, 2022, 12:00 PM

Nov 16, 2022, 12:00 PM

Sep 21, 2024, 3:00 AM

Aug 28, 2025, 9:34 PM

rules/emerging-malware.rules