751
Kerberos Master
Critical RiskTCP/UDP — Security & VPN
Port Overview
Port Number
751
Service Name
Kerberos Master
Transport Protocol
TCP/UDP
Category
Security & VPN
Security Risk
Critical
Port Range
Well-Known (0-1023)
What is Port 751?
Kerberos v4 master database administration service. Relies on cryptographically broken DES encryption. Should be disabled in all environments.
TCP/UDP
Security & VPN
Security Considerations
Port 751 (Kerberos Master) is classified as critical risk. This port should not be exposed to the public internet. The service transmits data without encryption, making it vulnerable to eavesdropping, credential theft, and man-in-the-middle attacks.
Recommendation: Block this port at the firewall. Use encrypted alternatives (SSH, SFTP, HTTPS) instead.