CernVM-FS is a solution to scalable, reliable and low-maintenance software distribution that is widely used in various High Energy Physics collaborations. The information that can be distributed by CernVM-FS is not limited to software but any other data. By default, the whole CernVM-FS repository containing all subdirectories and files is available to all users in read-only mode after mounting. This behaviour is not acceptable when CernVM-FS is used to distribute data that require different access levels. In this paper, we introduce an approach to apply data access policy to CernVM-FS so that a user can list and read only certain subdirectories and files according to his access level. All other subdirectories and files are hidden.