Rule History

alert tls $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Observed Cloudflare Tunneling Domain (argotunnel .com in TLS SNI)"; flow:established,to_server; tls.sni; dotprefix; content:".argotunnel.com"; endswith; fast_pattern; reference:url,www.guidepointsecurity.com/blog/tunnel-vision-cloudflared-abused-in-the-wild/; classtype:misc-activity; sid:2047123; rev:2; metadata:attack_target Client_Endpoint, created_at 2023_08_09, deployment Perimeter, performance_impact Low, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_09_01;)