hi, you can create a custom vulnerability signature to block it. But you have to Wireshark the traffic (down- or upload) with these files. In the pcap you can read out the "file-unknown-body" signature of that file which looks like \x3136977BB061728878688662\x with this condition you can configure a pattern-match and the action to block the traffic. More information are available here: https://live.paloaltonetworks.com/t5/Featured-Articles/Tips-amp-Tricks-Custom-Vulnerability/ta-p/71603 https://live.paloaltonetworks.com/t5/Documentation-Articles/Creating-Custom-Threat-Signatures/ta-p/58569?attachment-id=1097 https://live.paloaltonetworks.com/t5/APIs/Custom-signature-file-upload-blocking/m-p/25448/highlight/true#M650
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