Unable to use curl to transfer files from my machine to the server


I’m currently performing a Web Application penetration test and was able to gain RCE on the server, by using command injection on some PHP parameters. Thing is, when I try to use curl in the URL to connect back to a python webserver on my machine (in order to be able to transfer files from my machine to the server) I’m unable to do so. The website spends some time loading the page and then nothing happens.

I’m guessing that there is an ACL preventing outbound connections from the server, since there is one only allowing my IP to access the server, but I guess that it’s not bidirectional.

Any thoughts on how to be able to upload files to the server?

Thanks in advance!