- Run it in a Windows VM. The program could detect this and not phone home in this case, of course.
- Monitoring on network level (wireshark on same network, Pi-hole, router itself...). This is virtually impossible for the program to circumvent.
You could also audit the changes it made to the system (resorting to stuff like diffing disk images before/after if you really want zero trust) to verify that nothing sneaky was left after running the program once.
- Run it in a Windows VM. The program could detect this and not phone home in this case, of course.
- Monitoring on network level (wireshark on same network, Pi-hole, router itself...). This is virtually impossible for the program to circumvent.
You could also audit the changes it made to the system (resorting to stuff like diffing disk images before/after if you really want zero trust) to verify that nothing sneaky was left after running the program once.