Executive brief
Kimai is an open-source time-tracking and project management application. Before version 2.65.0, the API endpoints that remove team access to activities, projects, and customers fail to properly validate that the user has permission to manage those resources. An authenticated user with basic team-editing privileges can remove team access without the additional authorization check that should be required, allowing unauthorized access revocation.
Technical details
The vulnerability is an authorization bypass (CWE-862: Missing Authorization) in Kimai's REST API team management endpoints. The DELETE routes at /api/teams/{id}/activities/{activityId}, /api/teams/{id}/projects/{projectId}, and /api/teams/{id}/customers/{customerId} only check if the caller has edit_team permission on the target team, but fail to validate the permissions_activity (or equivalent) permission on the target activity, project, or customer—a check that is correctly enforced when granting access. An authenticated API user with edit_team permission can therefore revoke team access to resources they are not authorized to manage. The fix, released in version 2.65.0, adds the missing permission checks to all three revoke endpoints, ensuring that removing access requires the same authorization level as granting it.
Affected products
- Kimai Kimai before 2.65.0
Timeline
- 2026-08-19: disclosed
- 2026-09-02: advisory
- 2026-09-02: patched: Version 2.65.0 released