Use cURL to import files to the firewall.
Import Files to a Firewall or Panorama
Import files to a firewall: curl --form file=@filename “https://firewall/api/?query-parameters
Import files to a firewall via Panorama. First import the file to Panorama, then run a request batch upload-install op command: http://panorama/api/?type=op&cmd=<request><batch><anti-virus><upload-install><uploaded-file>your-file-name-here</uploaded-file><devices>serialnumber</devices></upload-install></anti-virus></batch></request>

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