alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET INFO PK/Compressed doc/JAR header"; flow:from_server,established; file_data; content:"|50 4B 03 04|"; depth:4; flowbits:set,ET.zipfile; flowbits:noalert; classtype:misc-activity; sid:2022055; rev:3; metadata:created_at 2015_11_10, deprecation_reason Relevance, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_24;)