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Port 2403 (taskmaster2000)

IANA assigns port 2403 to taskmaster2000: TaskMaster 2000 Web.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
taskmaster2000 TCP TaskMaster 2000 Web Ed Odjaghian -
taskmaster2000 UDP TaskMaster 2000 Web Ed Odjaghian -

Check what is listening on port 2403

Linux: is anything listening on TCP 2403?
sudo ss -tlnp 'sport = :2403'
Linux: UDP 2403
sudo ss -ulnp 'sport = :2403'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2403
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2403 '
Windows (Command Prompt)
netstat -ano | findstr :2403
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2403 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2403
From Windows
Test-NetConnection HOST -Port 2403
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2403

Block port 2403 in the firewall

ufw
sudo ufw deny 2403/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2403 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2403 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2403' -Direction Inbound -Protocol TCP -LocalPort 2403 -Action Block
ufw
sudo ufw deny 2403/udp
iptables
sudo iptables -A INPUT -p udp --dport 2403 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2403 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2403' -Direction Inbound -Protocol UDP -LocalPort 2403 -Action Block

Related ports

2402taskmaster20002401cvspserver2404iec-1042405trc-netpoll

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.