alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET USER_AGENTS Suspicious User Agent (agent)"; flow:established,to_server; http.header; content:!"cn.patch.battlenet.com.cn"; http.user_agent; content:"agent"; fast_pattern; startswith; http.host; content:!".battle.net"; endswith; content:!".blizzard.com"; endswith; content:!"blz"; depth:3; content:!".acronis.com"; endswith; classtype:trojan-activity; sid:2001891; rev:25; metadata:tls_state plaintext, created_at 2010_07_30, deployment Perimeter, deployment Internal, performance_impact Low, confidence High, signature_severity Major, updated_at 2025_07_31; target:src_ip;)