Internet-Security.com TCP port 7100 details

TCP port 7100 is used by the X Font Server (xfs), a component of the X Window System (X11) for serving fonts over the network.
Real-world examples include the xfs service shipped with X.Org/XFree86 on Linux (e.g., Red Hat Linux 7–9, RHEL 3–5, SUSE Linux Enterprise Server 9/10), Solaris 8/9 (CDE/DTLogin), HP-UX 11i, and IBM AIX 5.x.
Windows X server products such as Hummingbird Exceed and Xming can connect to an xfs on port 7100 to obtain fonts from Unix hosts.
Many legacy X terminals and centralized Unix desktop deployments configured clients with a font path like tcp/hostname:7100 to use a shared font server.
In modern setups, xfs is largely deprecated (fonts are usually handled locally or via fontconfig), but older systems and long-lived enterprise environments may still expose 7100/tcp.
Security note: Historically, exposed xfs services on 7100 have had remote denial-of-service and buffer-overflow vulnerabilities and have been targeted by scanners; best practice is to disable or firewall this port if not needed.

TCP 7100