CVE-2026-50186: fallo de gravedad alta en RARgames 4gaBoards

4gaBoards is a boards system for realtime project management. Prior to 3.3.8, 4gaBoards allows an authenticated project manager to supply traversal sequences in the filename parameter of GET /exports/:id/:filename. In server/api/controllers/boards/download.js, the decoded inputs.filename value is passed to path.join() beneath private/exports/<user_id>/ without containment validation. A crafted value such as ../ can select an arbitrary file readable by the server process, and the file is returned to the attacker. The fileStream close handler then passes the same path to fs.unlink(), deleting the selected file and potentially causing data loss or denial of service. This issue is fixed in version 3.3.8.