Vulnerability Discussion
Service configuration files enable or disable features of their respective services that if configured incorrectly can lead to insecure and vulnerable configurations; therefore, service configuration files should be owned by the correct group to prevent unauthorized changes.
Check
Verify the group ownership of all cron configuration files with the following command:
$ stat -c "%G %n" /etc/cron*
root /etc/cron.d
root /etc/cron.daily
root /etc/cron.deny
root /etc/cron.hourly
root /etc/cron.monthly
root /etc/crontab
root /etc/cron.weekly
If any crontab is not group owned by root, this is a finding.
Fix
Configure any cron configuration not group-owned by root with the following command:
$ sudo chgrp root [cron config file]