Port 2682: Unassigned — An empty address in the registered range

What Port 2682 Is

Port 2682 is unassigned. The Internet Assigned Numbers Authority (IANA), which maintains the official registry of port numbers, has not allocated this port to any protocol or service.¹

That isn't unusual. The registered port range (1024–49151) contains over 48,000 ports, and thousands of them are empty — either never claimed, or reclaimed after a service stopped using them.

The Registered Port Range

Ports fall into three ranges:

• Well-known ports (0–1023): Reserved for core Internet services. HTTP lives at 80, HTTPS at 443, SSH at 22. These require elevated privileges to bind on most operating systems.
• Registered ports (1024–49151): Available for applications and services to register with IANA. No special OS privileges required to bind. Port 2682 is here.
• Dynamic/ephemeral ports (49152–65535): Used temporarily by your OS for outgoing connections. Not registered at all.

Being in the registered range means port 2682 could be registered by anyone with a legitimate use case and a request to IANA. It just hasn't been.

Known Unofficial Uses

Port 2682 has no well-documented legitimate unofficial use. However, security databases have flagged it as having been used for malware callbacks — specifically as a command-and-control channel for trojans.²

This is a pattern across unassigned registered ports generally. Attackers pick quiet, unmonitored port numbers because most firewalls and intrusion detection systems focus on known-bad ports and known-good ports. An obscure number like 2682 attracts less scrutiny than, say, port 4444 (which is so commonly associated with Metasploit that it lights up every sensor in the room).

If you see unexpected traffic on port 2682, that's worth investigating.

How to Check What's Using This Port

On Linux or macOS:

# Show what process is listening on port 2682
sudo lsof -i :2682

# Or with ss (Linux):
sudo ss -tlnp | grep 2682

# Or with netstat:
sudo netstat -tulnp | grep 2682

On Windows (Command Prompt as Administrator):

netstat -ano | findstr :2682

The output will show the process ID (PID). You can then look up the PID in Task Manager or with:

# Linux/macOS
ps aux | grep <PID>

# Windows
tasklist | findstr <PID>

If something is listening on this port and you don't recognize it, that warrants a closer look.

Why Unassigned Ports Matter

The port registry exists so that services can reliably find each other. When you install software that listens on a registered port, the expectation is that IANA has recorded what that port is for — so that another application doesn't collide with it, and so that network administrators know what traffic to expect.

Unassigned ports are the gaps in that map. They're not forbidden, not dangerous by definition, and not empty in any absolute sense — any application can use them. They're just undocumented territory. And undocumented territory is where the interesting (and occasionally dangerous) things tend to happen.