CVE-2026-91984 [MEDIUM] – Vikunja before 2.6.0 fails to validate that user-supplied project_view_id in task-position

Vikunja before 2.6.0 fails to validate that user-supplied project_view_id in task-position requests belongs to the task’s project. Authenticated attackers can insert task position rows into arbitrary other tenant project views via POST or PUT task-position endpoints.