The remote host is missing an update to the system as announced in the referenced advisory.

Update your system with the appropriate patches or software upgrades.

The following packages are affected: wu-ftpd wu-ftpd+ipv6 CVE-2004-0148 wu-ftpd 2.6.2 and earlier, with the restricted-gid option enabled, allows local users to bypass access restrictions by changing the permissions to prevent access to their home directory, which causes wu-ftpd to use the root directory instead.