All ports

Port1977/UDP

tcoaddressbook

Port

1977

Protocol

UDP

Category

Registered

Service

tcoaddressbook

What is port 1977?

Port 1977/UDP is a Registered port, registered with IANA for specific applications. It is associated with the tcoaddressbook service.

TCO Address Book

Useful commands

nmapnmap -p 1977 -sV example.com
netcatnc -zv example.com 1977
curlcurl -v http://example.com:1977/
telnettelnet example.com 1977
bash(echo > /dev/udp/example.com/1977) 2>/dev/null

Firewall commands

UFWAllow
sudo ufw allow 1977/udp
Deny
sudo ufw deny 1977/udp
iptablesAllow
sudo iptables -A INPUT -p udp --dport 1977 -j ACCEPT
Deny
sudo iptables -D INPUT -p udp --dport 1977 -j ACCEPT
firewalldAllow
sudo firewall-cmd --permanent --add-port=1977/udp
WindowsAllow
netsh advfirewall firewall add rule name="Open Port 1977" dir=in action=allow protocol=UDP localport=1977

Security Risks

  • Unauthorized access to the service
  • Data exposure if the service is unauthenticated
  • Outdated versions with vulnerabilities
  • Incorrect service configuration

Frequently Asked Questions

What service runs on port 1977/UDP?

Port 1977/UDP is associated with the tcoaddressbook service. TCO Address Book

Is it safe to expose port 1977 to the Internet?

It depends on the service and configuration. Port 1977 (tcoaddressbook) is a Registered port. If you need to expose it, keep the service updated, use strong authentication, and configure a firewall. It's always recommended to restrict access by IP when possible.

How do I check if port 1977 is open?

You can use nmap: `nmap -p 1977 -sV example.com`, netcat: `nc -zv example.com 1977`, or the bash command: `(echo > /dev/udp/example.com/1977) 2>/dev/null && echo "Open" || echo "Closed"`.

How do I open or close port 1977 on my firewall?

On Linux with UFW: `sudo ufw allow 1977/udp` (open) or `sudo ufw deny 1977/udp` (close). With iptables: `sudo iptables -A INPUT -p udp --dport 1977 -j ACCEPT`. On Windows: `netsh advfirewall firewall add rule name="Open Port 1977" dir=in action=allow protocol=UDP localport=1977`.

What applications and services use port 1977?

Port 1977/UDP is used by the tcoaddressbook service. Specific uses depend on the software and configuration. Check our related tools section for more information.