Plane is an open-source project management tool. Prior to 1.4.0, Plane exposes the workspace-scoped GET /api/assets/v2/workspaces/{workspace_slug}/download/{asset_id}/ endpoint for project-bound FileAsset objects without enforcing access to the assets owning project. An authenticated user who belongs to the same workspace, is not a member of the victims secret project, and knows the target asset UUID can receive a 302 redirect to a signed download URL. The intended project-scoped route for the same asset correctly returns 403. Confirmed affected project-bound asset types are ISSUE_ATTACHMENT, COMMENT_DESCRIPTION, PAGE_DESCRIPTION, and PROJECT_COVER. This bypass exposes private file content protected by the secret project boundary. This issue is fixed in 1.4.0.
Weakness
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.
Extended Description
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.
Potential Mitigations
References
- https://github.com/makeplane/plane/commit/e63f0c3b3404d669ae05dd9050aab72292f87e5c
- https://github.com/makeplane/plane/pull/9372
- https://github.com/makeplane/plane/releases/tag/v1.4.0
- https://github.com/makeplane/plane/security/advisories/GHSA-wrrw-wvfv-67h7
- https://github.com/makeplane/plane/security/advisories/GHSA-wrrw-wvfv-67h7