Only allow explicitly defined host access to NFS exported filesystems and directories. Rationale: The NFS server should be configured to only allow explicitly defined hosts to mount filesystems from the server. If an unauthorized host is denied the permission to mount a filesystem, then the unauthorized users on that host will not be able to access the server's files. The default value of access allows any machine to mount any exported filesystems/directories.
Solution
Ensure that all exports defined in /etc/exports have explicit client access options which clearly define the host or hosts allowed access: Review the content of /etc/exports and that all exports have explicit access lists: showmount -e | grep '(everyone)' Ensure that each NFS export has an explicit access line, for example, modify: /export/repo (everyone) to: /export/repo x071 The option -c is used to specify clients permitted access: chnfsexp -d /export/repo -c x071 Default Value: N/A Additional Information: Reversion: Clear the client access specification by supplying the NULL string ('') as argument. chnfsexp -d /export/repo -c ''