UDP Port 68 – DHCP Client (Dynamic Host Configuration Protocol)

About UDP Port 68

Port 68 carries the IANA assignment for bootpc. The IANA description reads: ‘Bootstrap Protocol Client’. This port appears in 5 IDS rules and does not have notable malware activity indicators in our data.

IDS Rule References

5 IDS / security rules reference UDP port 68. Treat that number as context, not a danger score. Many detection rules are written against groups of ports rather than one service, web ports especially, so common web alternate ports inherit large counts while genuinely sensitive services can show few rules or none. Presence in IDS rules does not mean traffic on this port is malicious.

Rule categories (top 2): attempted-admin (3), attempted-user (2).

Sample rule descriptions for UDP port 68:

• OS-OTHER Malicious DHCP server bash environment variable injection attempt
• OS-LINUX Red Hat NetworkManager DHCP client command injection attempt
• OS-LINUX Red Hat NetworkManager DHCP client command injection attempt
• ET EXPLOIT Possible CVE-2014-6271 exploit attempt via malicious DHCP ACK
• ET EXPLOIT DynoRoot DHCP – Client Command Injection

Data Sources

This information is compiled from: IANA Service Name and Transport Protocol Port Number Registry, Emerging Threats Open Ruleset (BSD 2-Clause / GPLv2 per SID range), and Snort Community Rules (GPLv2).