CIS Ubuntu 14.04 LTS - 2.2.5 Ensure DHCP Server is not enabled

2.2.5 Ensure DHCP Server is not enabled (Scored)

Profile Applicability

• Level 1 - Server
• Level 1 - Workstation

Description

The Dynamic Host Configuration Protocol (DHCP) is a service that allows machines to be dynamically assigned IP addresses.

Rationale

Unless a system is specifically set up to act as a DHCP server, it is recommended that this service be deleted to reduce the potential attack surface.

Audit Procedure

Ensure no start conditions listed for isc-dhcp-server or isc-dhcp-server6:

initctl show-config isc-dhcp-server
initctl show-config isc-dhcp-server6

Verify the output shows no start conditions.

Expected Result

The isc-dhcp-server and isc-dhcp-server6 services should have no start conditions listed.

Remediation

Remove or comment out start lines in /etc/init/isc-dhcp-server.conf and /etc/init/isc-dhcp-server6.conf:

#start on runlevel [2345]

Default Value

DHCP server is not enabled by default.

References

1. More detailed documentation on DHCP is available at http://www.isc.org/software/dhcp.

• CIS Controls: 9.1 Limit Open Ports, Protocols, and Services

Profile

• Level 1 - Server
• Level 1 - Workstation