Port 67 (DHCP Server) — What It Is and How to Use It

Port 67 is the standard UDP port used by DHCP (Dynamic Host Configuration Protocol) servers to listen for DHCP client requests. It's crucial for automatic IP address assignment in networks, allowing devices to join and obtain network configurations without manual configuration.

Last updated: 2026-03-02

                Port Number
                67
            

Protocol DHCP Server

Common Use Cases

Automatic IP address assignment to devices joining a network.
Providing network configuration information like subnet mask, default gateway, and DNS server addresses.
Leasing IP addresses for a specific duration.

Check if Port 67 is Open

sudo netstat -an | grep ".67 "

Get-NetUDPEndpoint -LocalPort 67

⚠️ Security Note: Leaving port 67 open on a network without proper DHCP server configuration can lead to rogue DHCP servers assigning incorrect or malicious network settings. Ensure proper authentication and authorization mechanisms are in place to prevent unauthorized DHCP server operation.

Related Ports

Frequently Asked Questions

Is port 67 dangerous to leave open?

Leaving port 67 open on a network without a properly configured and secured DHCP server can be dangerous. Rogue DHCP servers can exploit this to assign incorrect or malicious network configurations, potentially leading to man-in-the-middle attacks or denial-of-service conditions.

What service uses port 67?

The DHCP server service uses port 67 to listen for DHCP client requests. This service is responsible for dynamically assigning IP addresses and other network configuration parameters to devices on the network.