alert tcp-pkt $EXTERNAL_NET any -> $HOME_NET any (msg:"ET INFO IDrive Backup Connection"; flow:established,to_client; stream_size:server,<,15; dsize:12; flowbits:set,ET.IDriveConnection; content:"@IDEVSD|3a 20|"; startswith; fast_pattern; content:"|0a|"; endswith; threshold:type limit, count 1, seconds 600, track by_dst; reference:url,www.idrive.com; classtype:misc-activity; sid:2046716; rev:1; metadata:attack_target Client_and_Server, created_at 2023_07_03, deployment Perimeter, performance_impact Low, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2023_07_03; target:dest_ip;)