I’m trying to get API responses from a backend service to make a server emulator for a game called NBA 2k17, but I can't get to them cause they are encrypted so I need to impersonate the client to get them but the server has mTLS on, do you know if this is even possible, cause it’s not stored anywhere locally. I also tried going into IDA pro to see if i can find it in there but I couldn't, it seems like the certificate isn't a pem certificate, it looks like it is in the der format so it would be pretty hard to spot inside ida.
have you tried using binwalk? it's an easy and quick tool that goes through the file and looks for headers of different file formats and can easily pick out if pem certificate is within the exe.
You could also probably wireshark the specific port the exe is using to communicate with the server and get the certificate that way?
I suggest you also look into Burp Suite as it might help you with decrypting the traffic and modifying it before sending it out to the main server.