A repo file is a configuration file for YUM repositories (software repositories) in Fedora. Typically, one repo file defines the details of one or more software repositories, such as where we will download the packages needed for installation or upgrades from. The settings in the repo file will be read and applied by YUM. If configured incorrectly, it can cause services to be unavailable.
If files have been added to /etc/yum.repos.d on the host, carefully check the host environment to ensure there has been no intrusion and change the host user passwords.