Typora 0.9.9.24.6 on macOS allows directory traversal, for execution of arbitrary programs, via a file:/// or ../ substring in a shared note.
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.