Port 2477: ssm-cvs — The Ghost Registration

What This Port Is

Port 2477 is not unassigned. IANA has it on the books as ssm-cvs — the SecurSight Certificate Validation Service, registered for both TCP and UDP.¹

SecurSight was a security product with its own namespace in the port registry. It claimed a cluster:

The ssm- prefix suggests a unified product suite. Someone built a PKI and certificate management platform, submitted port registration requests to IANA, and got them approved.

Then, apparently, the product ceased to exist. No active documentation survives online. No company presence. No users asking questions on forums. Just three port numbers in the IANA registry, pointing at something that used to be there.

Ghost Registrations

This is a known phenomenon in the registered ports range (1024–49151). When a company submits a port registration to IANA, that registration doesn't expire. IANA doesn't reclaim ports when products die. So the registry accumulates these permanent placeholders — officially occupied, practically empty.

Port 2477 is one of them. It's technically "taken," but nothing is running on it on any production system you're likely to encounter. If you see traffic on port 2477, it isn't SecurSight.

What Might Actually Be Running

If port 2477 is open on a system you're investigating, the possibilities are:

• Nothing: The port is listening but belongs to an unrelated service that chose this port arbitrarily
• Custom software: Internal applications sometimes bind to obscure registered ports because they're unlikely to conflict with anything else
• Malware: Obscure ports make convenient cover precisely because they appear registered and therefore "legitimate" in a cursory scan

How to Check

To see what's actually listening on port 2477:

Linux / macOS:

# Show the process listening on port 2477
ss -tlnp sport = :2477

# Or with lsof
lsof -i :2477

Windows:

netstat -ano | findstr :2477

The output will give you the PID, which you can look up in Task Manager or with tasklist /FI "PID eq <pid>".

The Registered Ports Range

Ports 1024–49151 were created to give applications a stable, non-conflicting address. IANA accepts registration requests, assigns port numbers, and publishes them so developers can avoid collisions. The system works reasonably well for active software.

For defunct products, it creates a quiet graveyard. The ports remain assigned. Nothing uses them. And occasionally someone writes a port scanner and wonders what ssm-cvs is.

Now you know.