Rule History

alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET MALWARE Possible APT29 CozyBear/SeaDaddy SSL/TLS Certificate Observed"; flow:established,to_client; tls.cert_subject; content:"C=--, ST=SomeState, L=SomeCity, O=SomeOrganization, OU=SomeOrganizationalUnit, CN=Cnyunwei.CNC"; content:"root@Cnyunwei.CNC"; fast_pattern; tls.cert_serial; content:"46:76"; classtype:targeted-activity; sid:2026538; rev:5; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2018_10_24, deployment Perimeter, confidence High, signature_severity Major, tag CozyBear, tag SeaDaddy, tag APT29, updated_at 2025_07_24;)