Network Port: 3000
Network Port Reference Guide
Registered Service Name
Node.js / React Development
Transport Protocol
TCP
Functional Overview
Port 3000 is the conventional default port for Node.js web applications, Express servers, React development servers, and Next.js dev instances.
Security Risks & Vulnerabilities
Development builds on port 3000 often run with verbose error stack traces, unminified source code, and exposed environment variables. Do not expose directly in production.
How to audit network port status
1. Scan Open Ports: Use our Port Scanner utility to verify if this port is actively listening on your host.
2. Verify Encryption: Audit the service layer to confirm SSL/TLS is protecting transmission payload.
3. Hardening Rules: Apply the firewall instructions below to shut down unauthorized inbound ports.
UFW Firewall Rules
Allow Command
sudo ufw allow 3000/tcp
Block Command
sudo ufw deny 3000/tcp
iptables Firewall Rules
Allow Command
sudo iptables -A INPUT -p tcp --dport 3000 -j ACCEPT
Block Command
sudo iptables -A INPUT -p tcp --dport 3000 -j DROP
Port Diagnostic Tools
Authoritative Standards
Port assignments governed by IANA. Well-known ports (0–1023) require IANA approval per RFC 6335.