Port 10000: Webmin
Port 10000 is the default port for Webmin, a web-based admin panel for Linux servers.
What runs on port 10000
Webmin lets you manage users, services, packages and files on a Linux system from a browser, served on TCP 10000. Port 10000 is also registered for NDMP, a backup protocol used by storage appliances, and some VPN clients have used it.
On a home network
Home servers and Raspberry Pis with Webmin installed listen on 10000, as do some backup appliances.
If port 10000 is reachable from the internet
Webmin gives root-level control, so an exposed instance is a high-value target. In 2019 it was found that some Webmin releases had been shipped with a backdoor planted in the build infrastructure, allowing remote command execution, and Webmin servers were scanned and attacked as a result. Keep it on the LAN or behind a VPN.
How to check whether it is open on your network
Check whether Webmin is installed and whether your router forwards 10000 to it. A LAN port scan shows which host serves it.
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