Title

The at.allow file must not have an extended ACL. (Cat II impact)

Discussion

File system extended ACLs provide access to files beyond what is allowed by the mode numbers of the files. Unauthorized modification of the at.allow file could result in Denial of Service to authorized at users and the granting of the ability to run at jobs to unauthorized users.

Check Content

Check the permissions of the file. # ls -lL /etc/cron.d/at.allow If the permissions include a "+", the file has an extended ACL and this is a finding.

Fix Text

Remove the extended ACL from the file. # chmod A- /etc/cron.d/at.allow

Additional Identifiers

Rule ID: SV-227759r603266_rule

Vulnerability ID: V-227759

Group Title: SRG-OS-000480

Expert Comments

CCIs tied to check.

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