alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Observed DNS over HTTPS Domain in TLS SNI (doh .mmmalia .com)"; flow:established,to_server; tls.sni; bsize:15; content:"doh.mmmalia.com"; fast_pattern; classtype:misc-activity; sid:2046658; rev:3; metadata:affected_product Any, created_at 2023_06_26, deployment Perimeter, performance_impact Low, confidence High, signature_severity Informational, tag DNS_over_HTTPS, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_12_01, mitre_tactic_id TA0011, mitre_tactic_name Command_And_Control, mitre_technique_id T1572, mitre_technique_name Protocol_Tunneling;)