Ensure at/cron is restricted to authorized users - cron.deny


On many systems, only the system administrator is authorized to schedule cron jobs. Using the cron.allow file to control who can run cron jobs enforces this policy. It is easier to manage an allow list than a deny list. In a deny list, you could potentially add a user ID to the system and forget to add it to the deny files.


Run the following commands to remove /etc/cron.deny and /etc/at.deny and create and set permissions and ownership for /etc/cron.allow and /etc/at.allow:
# rm /etc/cron.deny
# rm /etc/at.deny
# touch /etc/cron.allow
# touch /etc/at.allow
# chmod og-rwx /etc/cron.allow
# chmod og-rwx /etc/at.allow
# chown root:root /etc/cron.allow
# chown root:root /etc/at.allow

See Also