59 (Weakness Base)

Some people use the phrase "insecure temporary file" when referring to a link following weakness, but other weaknesses can produce insecure temporary files without any symlink involvement at all.

File processing, temporary files

Low to Medium

Resultant (Weakness is typically related to the presence of some other weaknesses)

Explicit (This is an explicit weakness resulting from behavior of the developer)

File/Directory

Follow the principle of least privilege when assigning access rights to files. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Link following vulnerabilities are Multi-factor Vulnerabilities (MFV). They are the combination of multiple elements: file or directory permissions, filename predictability, race conditions, and in some cases, a design limitation in which there is no mechanism for performing atomic file creation operations.

Some potentials factors are race conditions, permissions, predictability.

This is not OS specific.

Windows soft links can be exploited remotely since a ".LNK" file can be uploaded like a normal file.

UNIX hard links, and Windows hard/soft links are under-studied and under-reported.

PLOVER - Link Following

All