It gives hackers a roadmap of your entire server, making it easier to find weak points.
If you are more interested in the engineering side—how actual file search engines like (which powers Elasticsearch and Solr) work—the architecture is based on this seminal work: index of files
The is a double-edged sword of the web. On one hand, it is a transparent, efficient, and simple way to share files. On the other hand, it is a common source of data leaks and cyber vulnerabilities. It gives hackers a roadmap of your entire