CVE-2022-40734: UniSharp Laravel Filemanager directory traversal vulnerability

The vulnerability stems from using league/flysystem <2.0.0 which lacked proper path traversal detection. The primary fix was requiring flysystem^2.0 which added path normalization safeguards. While the Filemanager's download functionality handling the 'working_dir' parameter is the entry point, the actual vulnerable path resolution logic resides in flysystem's internal path handling (not directly in Filemanager's code). No specific functions in the Filemanager package itself are explicitly shown to contain vulnerable code - the weakness was in the dependency's path resolution capabilities rather than specific unsafe function implementations in the Filemanager.