Fox-IT DataDiode (aka Fox DataDiode) 3.4.3 suffers from a path traversal vulnerability with resultant arbitrary writing of files. A remote attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the downstream node user. Exploitation of this issue does not require user interaction.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.