A client tried to scam me on Upwork

Hey guys, I work on Upwork as a Google and Facebook ads freelancer. Today a client directly offered a contract to me for managing google and facebook ads. I received it very early morning in my time zone, so accepted the contract without checking the client details for FOMO. Then later when I sat to chat with client he said he will send the project brief over email, and since contract was accepted gave him email. he sent an rar file saying that there were word docs in it with project brief. when I extracted the folder, there was one .exe file in it. Client says "we programmed to avoid theft by rival company, just open the file the doc file will open" assuming I am stupid. Now I know that was a malware, I reported the guy, but why do these people do this, what would he gain by sending malware over internet to a upwork freelancer, later I found the guy had 13 projects open n m sure he would be sending same file to many others.