alert http $HOME_NET any -> $EXTERNAL_NET !$HTTP_PORTS (msg:"ET INFO HTTP Request on Unusual Port Possibly Hostile"; flow:established,to_server; flowbits:isnotset,et.httpproto; flowbits:isnotset,ET.knowitsnothttpnow; flowbits:set,et.httpproto; flowbits:set,ET.knowitsnothttpnow; threshold:type limit, count 1, seconds 30, track by_dst; classtype:policy-violation; sid:2006408; rev:15; metadata:created_at 2010_07_30, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_03_14;)