Port 10335 — Unassigned, Registered Range

What Port 10335 Is

Port 10335 is an unassigned port in the registered port range (1024-49151). This means it sits in the middle tier of the Internet's port system: below the well-known system ports (0-1023) that carry protocols like HTTP, SMTP, and SSH, and above the dynamic/private ports (49152-65535) that applications claim temporarily.

IANA, the Internet Assigned Numbers Authority, has not assigned port 10335 to any official protocol or service. This makes it a blank space on the port map.

What That Actually Means

Unassigned doesn't mean unused. It means no one filed the paperwork. The port is fair game for:

• Proprietary software that needs a listening port and picked a number
• Custom in-house applications at companies that never registered with IANA
• Malware that needs command-and-control channels
• Services being tested before moving to an official registration
• Niche tools and protocols too specialized or too new to have IANA assignments

Known Use: Malware

Security research indicates port 10335 appears in malware analysis databases as associated with trojan activity.¹ The port has been observed in suspicious network traffic patterns captured in threat intelligence systems. This doesn't mean port 10335 is always malicious—malware is just one of the things that uses unassigned ports because they're less monitored than official ones.

How to Check What's Listening

On your own system, find what (if anything) is listening on port 10335:

macOS/Linux:

lsof -i :10335          # See what process is listening
netstat -an | grep 10335  # Check if anything is listening at all

Windows:

netstat -ano | findstr :10335

If nothing shows up, the port is quiet on your machine.

On a remote system, scanning is the only way to know:

nmap -p 10335 target-ip
curl telnet://target-ip:10335  # Very basic connectivity check

Why Unassigned Ports Matter

The registered port range (1024-49151) has about 48,000 port numbers. IANA has formally assigned services to roughly 500-1000 of them. That leaves tens of thousands of unassigned ports—a vast frontier where legitimate and malicious software coexist without formal oversight.

Attackers use unassigned ports specifically because security monitoring often focuses on "known" ports. Port 10335 is quiet. That makes it useful for hiding things.