Using a GPL external executable within a commercial web application

I want to develop an idea for a commercial web application.

To provide that service (and get paid for it), I need to use an external executable software somewhere in the process, which is licensed under GPLv2 or later. I only need to install it (separately) in the server. Then, send it some parameters from my web application, execute it, and get its output back again to my web flow.

Will I have any legal problem doing this?

What kind of implications could the use of that external executable have?

Thanks in advance.