pwn.college is an education platform to learn about, and practice, core cybersecurity concepts in a hands-on fashion. Incorrect symlink checks on user specified dojos allows for users (admin not required) to perform an LFI from the CTFd container. When a user clones or updates repositories, a check is performed to see if the repository had contained any symlinks. A malicious user could craft a repository with symlinks pointed to sensitive files and then retrieve them using the CTFd website.
https://github.com/pwncollege/dojo/security/advisories/GHSA-fcq8-jqq5-9xmh