alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET WEB_CLIENT Download of Multimedia Content flowbit set"; flow:established,to_client; flowbits:set,ET.Multimedia.Download; flowbits:noalert; file.data; content:"|00 00 00|"; startswith; content:"|66 74 79 70|"; distance:1; within:4; fast_pattern; reference:url,www.garykessler.net/library/file_sigs.html; classtype:misc-activity; sid:2024689; rev:6; metadata:created_at 2017_09_08, deprecation_reason Relevance, signature_severity Informational, tag noalert, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_04_19;)