alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET HUNTING SUSPICIOUS Possible automated connectivity check (www.google.com)"; flow:established,to_server; urilen:1; http.method; content:"GET"; http.host; bsize:10; content:"google.com"; fast_pattern; http.header_names; to_lowercase; content:!"|0d 0a|accept"; content:!"|0d 0a|user-agent|0d 0a|"; content:!"|0d 0a|cache-"; content:!"|0d 0a|pragma"; content:!"|0d 0a|referer|0d 0a|"; content:!"|0d 0a|content"; threshold:type both,track by_src,count 2,seconds 10; classtype:bad-unknown; sid:2018430; rev:7; metadata:affected_product Web_Browsers, affected_product Web_Browser_Plugins, attack_target Client_Endpoint, created_at 2014_04_30, deployment Perimeter, performance_impact Significant, confidence Medium, signature_severity Major, tag Web_Client_Attacks, updated_at 2024_05_06;)