Title

Cron and crontab directories must not have extended ACLs. (Cat II impact)

Discussion

To protect the integrity of scheduled system jobs and to prevent malicious modification to these jobs, crontab files must be secured. ACLs on cron and crontab directories may provide unauthorized access to these directories. Unauthorized modifications to these directories or their contents may result in the addition of unauthorized cron jobs or deny service to authorized cron jobs.

Check Content

Check the permissions of the crontab directories. # ls -ld /var/spool/cron/crontabs/ If the permissions include a "+", the directory has an extended ACL and this is a finding.

Fix Text

Remove the extended ACL from the directory. # chmod A- /var/spool/cron/crontabs/

Additional Identifiers

Rule ID: SV-227749r603266_rule

Vulnerability ID: V-227749

Group Title: SRG-OS-000480

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.