A method for secure portable operating system interface (POSIX) directory traversing for opening and accessing files by inode number. The method includes receiving, by a process executed by a processor, a request for a ticket for traversing a file system. The process generates a secure key for a unique handle object based on the request for the ticket. An authentication code is generated for the ticket using a numeric file identifier and the secure key. In response to reading a directory with POSIX x and r permissions according to directory permission bits or an access control list (ACL), the ticket is returned including ticket information including the numeric file identifier, generation information and the authentication code. In response to a request to open a directory, the ticket information is validated based on the secure key. A directory is opened for reading using the validated ticket information and the unique handle.