Code [cron001w]
The listed cron entry does not use a full pathname for the listed command (or if a shell is specified, the name of the shell script). Full pathnames should be used for cron entries.
Code [cron002]
The listed cron entry uses an executable or file which is not owned by the owner of the cron entry, and is also not owned by a system account (root or bin, etc). For root cron entries, these are especially dangerous. Note that the actual problem may be with a directory in the path to the file, not the file itself.
Code [cron003]
The listed cron entry uses a file or executable which has group write permissions, world write permissions or both. This can allow the system to be compromised. For root cron entries, this is especially dangerous. Note that the actual problem may be with a directory in the path to the file, not the file itself.
Code [cron004w]
There is no crontab for the superuser account this is not in itself an error since many systems might ship without one and use other methods (/etc/cron* files) to run programs as root. However, if there is no method for root to run scripts some system checking scripts (like tiger) might not get executed at all.
Code [cron005w]
Cron allows users to submit jobs for the system to do at a particular, possibly recurring time. It can be very useful, but also has a very real potential for abuse by either users or system crackers. Users can be restricted to use cron by creating a /etc/cron.allow file holding only system administrators.