CVE-2025-49135: CVAT missing validation for in-progress backup upload names

CVAT is an open source interactive video and image annotation tool for computer vision. Versions 2.2.0 through 2.39.0 have no validation during the import process of a project or task backup to check that the filename specified in the query parameter refers to a TUS-uploaded file belonging to the same user. As a result, if an attacker with a CVAT account and a user role knows the filenames of other users' uploads, they could potentially access and steal data by creating projects or tasks using those files. This issue does not affect annotation or dataset TUS uploads, since in this case object-specific temporary directories are used. Users should upgrade to CVAT 2.40.0 or a later version to receive a patch. No known workarounds are available.