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Programs with elevated privileges may need to write files to directories owned by unprivileged users. One example is a mail daemon that reads a mail message from one user and places it in a directory owned by another user. In such cases, the mail daemon should assume the privileges of a user when reading or writing files on behalf of that user, in which case all file access should occur in secure directories relative to that user. When a program with elevated privileges must write files on its own behalf, these files should be in secure directories relative to the privileges of the program (such as directories accessible only by the system administrator).
Exceptions
FIO00-J-EX0: Programs that operate on single-user systems or on systems that have no shared directories or no possibility of file system vulnerabilities do not need to ensure that files are maintained in secure directories before operating on them.
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