alert http $HOME_NET 1024: -> $EXTERNAL_NET any (msg:"ET USER_AGENTS Suspicious Win32 User Agent"; flow:to_server,established; http.header; content:"User-Agent|3a 20|Win32"; nocase; classtype:trojan-activity; sid:2012249; rev:5; metadata:created_at 2011_02_02, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_04_23;)