org.gaul S3Proxy implements the S3 API and proxies requests. Users of the filesystem and filesystem-nio2 storage backends could unintentionally expose local files to users. This issue has been addressed in version 2.6.0. Users are advised to upgrade. There are no known workarounds for this vulnerability.
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.