Port 10386 — Unassigned, Unofficially Used

What This Port Is

Port 10386 belongs to the registered port range (1024–49151). This means it's administratively available: anyone can petition IANA for an official assignment, but currently, port 10386 has no standardized, globally recognized service attached to it. ¹

Why This Matters

The registered range exists as the Internet's middle ground. The system ports (0–1023) are jealously guarded by IANA for universally recognized protocols like HTTP, SSH, and SMTP. The dynamic range (49152–65535) is free-for-all space for temporary connections. But the registered range is where real applications live—not system-level protocols, but actual software that needs a stable port number. ²

Port 10386 never got there. It remains unassigned.

Unofficial Uses

Kaseya VSA, a remote management and endpoint security platform used across thousands of enterprises, references port 10386 in its installation documentation. ³ This doesn't mean it's officially assigned to Kaseya—it means some configuration or internal process at Kaseya has historically associated with this port number. Whether other applications use it is unclear from public records.

This is actually the pattern for unassigned registered ports: they exist in a gray zone where private applications occasionally claim them for internal use, but nobody filed the paperwork with IANA.

How to Check What's Using It

On Linux/macOS:

lsof -i :10386
ss -tulnp | grep 10386
netstat -tulpn | grep 10386

On Windows:

netstat -bano | findstr 10386
netstat -ano | findstr 10386

These commands will show you if anything on your system is listening on port 10386, and (on Linux) which process is doing it.

To check globally: If you're scanning a remote system, port 10386 might respond to a connection attempt:

nc -zv hostname 10386
nmap -p 10386 hostname

Why Unassigned Ports Exist

IANA has 49,151 registered ports available but only a few thousand are officially assigned. ⁴ The rest exist in potential—waiting for a company to need a permanent port, submit documentation, get approved, and make it official. Most never will be.

Port 10386 is democracy in action: it's yours if you want it, nobody else's if you don't, and the Internet doesn't care either way. But if you're finding it in your logs or firewall rules, something has quietly claimed it.