cyberstrikeus CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - 5.1.7
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Description
The /etc/cron.d directory contains system cron jobs that need to run in a similar manner to the hourly, daily, weekly and monthly jobs from /etc/crontab, but require more granular control as to when they run. The files in this directory cannot be manipulated by the crontab command, but are instead edited by system administrators using a text editor. The commands below restrict read/write and search access to user and group root, preventing regular users from accessing this directory.
Note: Other methods, such as systemd timers, exist for scheduling jobs. If another method is used, cron should be removed, and the alternate method should be secured in accordance with local site policy.
Rationale
Granting write access to this directory for non-privileged users could provide them the means for gaining unauthorized elevated privileges. Granting read access to this directory could give an unprivileged user insight in how to gain elevated privileges or circumvent auditing controls.
Impact
None.
Audit Procedure
Command Line
Run the following command and verify Uid and Gid are both 0/root and Access does not grant permissions to group or other:
stat /etc/cron.d/
Expected Result
Access: (0700/drwx------) Uid: ( 0/ root) Gid: ( 0/ root)
Remediation
Command Line
Run the following commands to set ownership and permissions on the /etc/cron.d directory:
chown root:root /etc/cron.d/
chmod og-rwx /etc/cron.d/
Default Value
By default, /etc/cron.d is owned by root:root with permissions 0755.
References
None.
CIS Controls
| Controls Version | Control |
|---|---|
| v7 | 14.6 Protect Information through Access Control Lists |
Assessment Status
Automated