The software uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize '.../...//' (doubled triple dot slash) sequences that can resolve to a location that is outside of that directory.This allows attackers to traverse the file system to access files or directories that are outside of the restricted directory.The '.../...//' manipulation is useful for bypassing some path traversal protection schemes. If "../" is filtered in a sequential fashion, as done by some regular expression engines, then ".../...//" can collapse into the "../" unsafe value (CWE-182). Removing the first "../" yields "....//"; the second removal yields "../". Depending on the algorithm, the software could be susceptible to CWE-34 but not CWE-35, or vice versa.