SimpleHelp remote support software v5.5.7 and before allows admin users to upload arbitrary files anywhere on the file system by uploading a crafted zip file (i.e. zip slip). This can be exploited to execute arbitrary code on the host in the context of the SimpleHelp server user.
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
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.