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Problem Description:- Malware hash external list.
Unfortunately there won't be any publicly available article from FGT.
You can try below Hash from vriustotal.
You have to create hash on based of file (pdf, exe, jpg).
Global -> Security Fabric -> Fabric Connectors and select 'Create New
You can create your hash with help of below video. It explain very well to create hash and try blocking it with "External Malware Integration".
You can go through with below article for configuration.
Let us know if this helps.