Disable ntpdate Service (ntpdate)

Docs > Datadog Security > OOTB Rules > Disable ntpdate Service (ntpdate)

Description

The ntpdate service sets the local hardware clock by polling NTP servers when the system boots. It synchronizes to the NTP servers listed in /etc/ntp/step-tickers or /etc/ntp.conf and then sets the local hardware clock to the newly synchronized system time.

The ntpdate service can be disabled with the following command:

$ sudo systemctl disable ntpdate.service

Rationale

The ntpdate service may only be suitable for systems which are rebooted frequently enough that clock drift does not cause problems between reboots. In any event, the functionality of the ntpdate service is now available in the ntpd program and should be considered deprecated.

Remediation

Shell script

The following script can be run on the host to remediate the issue.

#!/bin/bash

SYSTEMCTL_EXEC='/usr/bin/systemctl'
"$SYSTEMCTL_EXEC" stop 'ntpdate.service'
"$SYSTEMCTL_EXEC" disable 'ntpdate.service'
# Disable socket activation if we have a unit file for it
"$SYSTEMCTL_EXEC" list-unit-files | grep -q '^ntpdate.socket\>' && "$SYSTEMCTL_EXEC" disable 'ntpdate.socket'
# The service may not be running because it has been started and failed,
# so let's reset the state so OVAL checks pass.
# Service should be 'inactive', not 'failed' after reboot though.
"$SYSTEMCTL_EXEC" reset-failed 'ntpdate.service'

Ansible playbook

The following playbook can be run with Ansible to remediate the issue.

- name: Disable service ntpdate
  service:
    name: "{{item}}"
    enabled: "no"
    state: "stopped"
  register: service_result
  failed_when: "service_result is failed and ('Could not find the requested service' not in service_result.msg)"
  with_items:
    - ntpdate
  tags:
    - service_ntpdate_disabled
    - unknown_severity
    - disable_strategy
    - low_complexity
    - low_disruption
    - NIST-800-53-AC-17(8)
    - NIST-800-53-CM-7


- name: Disable socket of service ntpdate if applicable
  service:
    name: "{{item}}"
    enabled: "no"
    state: "stopped"
  register: socket_result
  failed_when: "socket_result is failed and ('Could not find the requested service' not in socket_result.msg)"
  with_items:
    - ntpdate.socket
  tags:
    - service_ntpdate_disabled
    - unknown_severity
    - disable_strategy
    - low_complexity
    - low_disruption
    - NIST-800-53-AC-17(8)
    - NIST-800-53-CM-7