Internet-Security.com TCP port 7878 details

Radarr (movie collection manager) uses TCP port 7878 by default for its web interface and API (e.g., http://localhost:7878).
This same default is common in packaged deployments on Unraid, Synology/QNAP (via Docker), and Windows/Linux installers of Radarr.
Various home-media automation stacks (e.g., “*arr*” suites with Sonarr/Lidarr) commonly expose Radarr specifically on 7878 in reverse proxies like Nginx/Traefik.
Not specifically tied to a well-known exploitation framework, but misconfigured internet-exposed Radarr instances on 7878 have been targets for scanning and takeover attempts (e.g., abusing weak credentials or API keys).

TCP 7878