Paper 2020/457

Cryptographic Scheme for analyzing protected files on Sandboxes and share them privately

Ahmad Almorabea

Abstract

Sharing a documents with a business partner is not always easy. since the sender often need to send sensitive information. and he want to ensure the integrity and the secrecy of the document. And in the same time. he wants to insure that only the specific individual or the recipients are the only one who can view it. So people tend to use some encryption software. or protecting the document with some sort of password. and then share the password with the recipient to make sure he is the only one who can view the document. But Unfortunately in many situations this method will not work. for a particular reason. and that is once the sender send an email. the email will start his journey into the company's network. and it will pass through many appliances. such Firewalls, Exchange servers and most likely Sandboxes. And there is one feature in sandboxes that we are interested in. once the sandbox sees an encrypted file or a protected file. it will immediately stop the email and quarantine it. because the sandbox couldn’t scan it. or couldn’t ensure if it’s malicious or not. so it will stop it for further analysis or a manual analysis depending on the procedures there. And such an action could stop a valid business transaction. and it could cause some business interruption. In this paper we will introduce a scheme for allowing the share of protected files. and analyzing them through Sandboxes. and in the same time no one can view it except for the authorized people.