Disallow segments that don't exist

What is occurring is that the template is targeting the last segment in the url, making it possible for multiple paths to exist. How do I disallow segments that don’t exist?

For example: https://www.SITE.com/lasers/main/mephisto-lasers https://www.SITE.com/lasers/main/test/test/mephisto-lasers

test/test does not represent anything. I need to send that to a 404 page.