The ftpusers file must not have an extended ACL.

From SUSE Linux Enterprise Server v11 for System z Security Technical Implementation Guide

Associated with: CCI-000225

SV-45884r1_rule The ftpusers file must not have an extended ACL.

Vulnerability discussion

Excessive permissions on the ftpusers file could permit unauthorized modification. Unauthorized modification could result in Denial of Service to authorized FTP users or permit unauthorized users to access the FTP service.

Check content

Check the permissions of the /etc/ftpusers file. # ls -lL /etc/ftpusers /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers If the permissions include a '+', the file has an extended ACL. If the file has an extended ACL and it has not been documented with the IAO, this is a finding.

Fix text

Remove the extended ACL from the file. # setfacl --remove-all /etc/ftpusers /etc/vsftpd.ftpusers /etc/vsftpd/ftpusers

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