In Amanda 3.5.1, an information leak vulnerability was found in the calcsize SUID binary. An attacker can abuse this vulnerability to know if a directory exists or not anywhere in the fs. The binary will use `opendir()` as root directly without checking the path, letting the attacker provide an arbitrary path.
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.