CVE-2026-55066 Vikunja: Cross-tenant IDOR in kanban move-task endpoint via unauthorized body task_id

Vikunja is an open-source self-hosted task management platform. Prior to 2.4.0, POST /api/v1/projects/project/views/view/buckets/bucket/tasks accepts a body supplied taskid but TaskBucket.CanUpdate in pkg/models/kanbantaskbucket.go authorizes only the project, view, and bucket from the URL...