Rule History

alert tls $EXTERNAL_NET any -> $HOME_NET any (msg:"ET INFO DNS Over HTTPS Certificate Inbound (cnnic-chinatelecom-chinamobile-chinaunicom--bili-d .dahi .icu)"; flow:established,to_client; tls.cert_subject; content:"cnnic-chinatelecom-chinamobile-chinaunicom--bili-d.dahi.icu"; fast_pattern; pcre:"/CN=(?:[^\r\n]+?\.)?cnnic\-chinatelecom\-chinamobile\-chinaunicom\-\-bili\-d\.dahi\.icu(?!\.)/"; reference:url,github.com/curl/curl/wiki/DNS-over-HTTPS; classtype:misc-activity; sid:2045823; rev:1; metadata:attack_target Client_Endpoint, created_at 2023_05_23, deployment Perimeter, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_05_23;)