← Port Encyclopedia
123

NTP

UDP
System Medium Risk
Network Time Protocol — time synchronization, NTP amplification DDoS attacks

🔍 How to Scan Port 123

nmap -sV -p 123 target
nmap -sV -sC --script=banner -p 123 target
nc -zv target 123

🛡️ Security Considerations

  • Scan port 123 with nmap -sV to identify the exact service and version
  • If NTP is not needed, close or firewall this port immediately
  • Check for default credentials if a management interface runs on this port
  • Use searchsploit ntp to find known exploits
  • Monitor traffic on port 123 with Wireshark or tcpdump for anomalies
  • Ensure the service is patched to the latest version to prevent known CVE exploitation

🔗 Related System Ports

Port 1
TCPMUX
Port 5
RJE
Port 7
Echo
Port 9
Discard
Port 11
systat
Port 13
Daytime
Port 17
QOTD
Port 19
Chargen
Port 37
Time
Port 79
Finger
Port 111
RPCbind
Port 113
Ident

📍 Nearby Ports

Port 118
Port-118
Port 119
NNTP
Port 120
Port-120
Port 121
Port-121
Port 122
Port-122
Port 124
Port-124
Port 125
Port-125
Port 126
Port-126
Port 127
Port-127
Port 128
Port-128
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