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.
The system’s authorization functionality does not prevent one user from gaining access to another user’s data or record by modifying the key value identifying the data.
Retrieval of a user record occurs in the system based on some key value that is under user control. The key would typically identify a user-related record stored in the system and would be used to lookup that record for presentation to the user. It is likely that an attacker would have to be an authenticated user in the system. However, the authorization process would not properly check the data access operation to ensure that the authenticated user performing the operation has sufficient entitlements to perform the requested data access, hence bypassing any other authorization checks present in the system. For example, attackers can look at places where user specific data is retrieved (e.g. search screens) and determine whether the key for the item being looked up is controllable externally. The key may be a hidden field in the HTML form field, might be passed as a URL parameter or as an unencrypted cookie variable, then in each of these cases it will be possible to tamper with the key value. One manifestation of this weakness is when a system uses sequential or otherwise easily-guessable session IDs that would allow one user to easily switch to another user’s session and read/modify their data.