MPXJ is an open source library to read and write project plans from a variety of file formats and databases. The patch for the historical vulnerability CVE-2020-35460 in MPXJ is incomplete as there is still a possibility that a malicious path could be constructed which would not be picked up by the original fix and allow files to be written to arbitrary locations. The issue is addressed in MPXJ version 13.5.1.
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.