alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO Proxy Connection detected"; flow:established,to_server; http.header_names; to_lowercase; content:"|0d 0a|proxy-connection|0d 0a|"; classtype:attempted-user; sid:2001449; rev:10; metadata:created_at 2010_07_30, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_05_07;)