HTTPfy

Port 62 (acas)

IANA assigns port 62 to acas: ACA Services.

Well-known (system) port, 0-1023 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
acas TCP ACA Services E Wald -
acas UDP ACA Services E Wald -

Check what is listening on port 62

Linux: is anything listening on TCP 62?
sudo ss -tlnp 'sport = :62'
Linux: UDP 62
sudo ss -ulnp 'sport = :62'
Linux / macOS: which process owns the port
sudo lsof -nP -i :62
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':62 '
Windows (Command Prompt)
netstat -ano | findstr :62
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 62 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 62
From Windows
Test-NetConnection HOST -Port 62
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 62

Block port 62 in the firewall

ufw
sudo ufw deny 62/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 62 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 62 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 62' -Direction Inbound -Protocol TCP -LocalPort 62 -Action Block
ufw
sudo ufw deny 62/udp
iptables
sudo iptables -A INPUT -p udp --dport 62 -j DROP
nftables
sudo nft add rule inet filter input udp dport 62 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 62' -Direction Inbound -Protocol UDP -LocalPort 62 -Action Block

Related ports

58xns-mail59any private file service63whoispp, whois++64covia

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