CyberHunter
// Monitoring & logging

Port 1993: cisco SNMP TCP port

Port 1993 is assigned by IANA to snmp-tcp-port (cisco SNMP TCP port).

1993

How snmp-tcp-port works

Monitoring & logging
monitoringdevicesnmp-tcp-port monitoringdevicesnmp-tcp-port

The monitoring server collects metrics, alerts or logs from devices over port 1993.

Transport
TCP · UDP
Exposure risk
not rated depends on the program listening
Encryption
Unknownnot stated by the registry
IANA status
Assigned1 registered service
Range
Registered (1024-49151)
01 Security

Is port 1993 dangerous?

We have no specific security note for port 1993. Its risk depends on the program actually listening on it. General advice for monitoring & logging services:

  • Restrict management and monitoring protocols to the monitoring network.
  • Replace community strings and default credentials.
  • Send logs over TLS.
02 Registry

IANA registry entries for port 1993

ServicePortTransportDescriptionReferenceUpdated
snmp-tcp-port 1993 TCP, UDP cisco SNMP TCP port - -

// source: IANA service name and port number registry

03 Check it

Which program uses port 1993, and is it reachable?

Linux

sudo ss -ltnup 'sport = :1993'      # process listening on 1993
sudo lsof -nP -i :1993

macOS

sudo lsof -nP -i :1993

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 1993 -State Listen | Select LocalAddress, OwningProcess
Get-NetUDPEndpoint -LocalPort 1993
netstat -ano | findstr :1993

From another machine

nmap -p 1993 -sV <host>
sudo nmap -sU -p 1993 <host>
nc -zv <host> 1993

Block it in the firewall

sudo ufw deny 1993/tcp                                         # Linux (ufw)
New-NetFirewallRule -DisplayName "Block 1993" -Direction Inbound -LocalPort 1993 -Protocol TCP -Action Block  # Windows
04 FAQ
What is port 1993 used for?

Port 1993 is assigned by IANA to snmp-tcp-port (cisco SNMP TCP port).

Is port 1993 TCP or UDP?

Port 1993 is registered for TCP and UDP.

Is it safe to open port 1993?

It depends on the program that listens on it. Open it only for a service you know and only to the networks that need it. Restrict management and monitoring protocols to the monitoring network.

How do I check if port 1993 is open?

On Linux run "ss -ltnup 'sport = :1993'", on macOS "lsof -nP -i :1993", and on Windows "netstat -ano | findstr :1993" to see the local process. From another machine, "nmap -p 1993 <host>" shows whether it is reachable.

05 Related